JP7528015B2 - Endoscope equipment - Google Patents

Description

This disclosure relates to an endoscope device.

Typically, an endoscope device has a long, slender, tubular insertion section that is inserted into the subject, an operation section that is provided at the base end of the insertion section and that operates the insertion section and other parts of the endoscope device, and a flexible connecting tube (universal cord) that extends from the operation section and connects the endoscope device to a processor (signal processing device). At the tip of the insertion section, an imaging device is provided that incorporates an imaging element such as a CCD that captures an image of the observation area.

The endoscope device is used while connected to the processor via a connecting flexible tube, and transmits control signals and video signals captured by the imaging device to and from the processor, and also receives driving power from the processor. Meanwhile, the processor generates an image of the observation location inside the subject based on the video signal captured by the imaging device at the tip of the insertion portion, which is transmitted from the endoscope device.

Incidentally, imaging elements (image sensors) such as CCD and CMOS are becoming increasingly dense and pixel-rich so that they can capture clearer images. Endoscope devices are also expected to use such high-density, high-pixel imaging elements to obtain clearer images of observed locations. However, when using high-density, high-pixel imaging elements in the imaging device of an endoscope device, it becomes necessary to transmit the video signal, which has an increased amount of information due to the high density and high pixel count of the imaging element, between the imaging device at the tip of the insertion section and the processor at high speed and without delay. For this reason, an optical transmission module that transmits the imaging element and the video signal from the imaging element to the processor, as shown in Patent Documents 1 and 2, is built into the inside of the tip of the insertion section of the endoscope device.

Patent No. 6300442 International Publication No. 2018/092233

In an endoscope device, since the insertion section is inserted into the subject, it is necessary to make the outer diameter and length of the hard part (the non-flexible/extendable part at the tip) at the tip of the insertion section, into which the imaging element and light transmission module are incorporated, as small as possible to make the device as minimally invasive as possible. For this reason, it is necessary to make the size of the light transmission module that is incorporated together with the imaging element inside the hard part at the tip of the insertion section as small as possible.

However, in the optical transmission modules shown in Patent Documents 1 and 2, an FPC board is used in which an adhesive is applied to the bent portion bent at a right angle to hold and fix the bent shape, and a photoelectric conversion element and an IC for driving the photoelectric conversion element are mounted on the board surface inside the bent portion, but there is a possibility that the bent shape of the FPC board bent at a right angle may not be stable during the manufacture of the optical transmission module.

In addition, the image sensor as an imaging device that includes an image sensor and the IC for driving the photoelectric conversion element in the optical transmission module are each heat-generating components, so heat dissipation measures are also required at the tip of the insertion portion of the endoscope device to ensure stable operation of each of these heat-generating components.

However, in Patent Document 1, the arrangement of the optical element and the driving IC is considered in relation to the length of the optical transmission module, and in Patent Document 2, the connection arrangement of the signal cable is considered, so no consideration was given at all to heat dissipation measures for each of the heat-generating components, such as the image sensor and the IC for driving the photoelectric conversion element.

In consideration of the particular problems associated with the above-mentioned endoscope device, the present disclosure provides an endoscope device that is miniaturized while providing heat dissipation measures for the optical transmission module placed inside the tip of the insertion section, thereby improving its performance.

In order to solve the above problems, the present disclosure provides:
An endoscope apparatus comprising: an insertion section having an imaging device at a tip end thereof that is inserted into a subject, the imaging device capturing images of the inside of the subject; an operation section that is connected to a base end of the insertion section and operates the insertion section; and a flexible connecting tube section having one end connected to the operation section and the other end equipped with a connection section with a processor,
an optical transmission module, comprising: a first substrate on which a photoelectric conversion element for converting an electrical signal into an optical signal and a photoelectric conversion element drive circuit for causing the electrical signal output of the imaging device to be output as an optical signal from the photoelectric conversion element are mounted; an exposed portion of the photoelectric conversion element and the photoelectric conversion element drive circuit is formed with a guide holder for positioning and holding one end of an optical signal transmission line for transmitting the optical signal output of the photoelectric conversion element with respect to the photoelectric conversion element; and the exposed portion is molded and concealed with a heat dissipation member;
an optical transmission module configured by attaching the optical transmission module to a second board on which the imaging device is attached;
Including,
The endoscope apparatus includes an endoscope device in which the photoelectric conversion element, the photoelectric conversion element drive circuit section, and the imaging device are integrally assembled inside the distal end of the insertion section by the optical transmission module.

According to the present disclosure, in an optical transmission module in which a photoelectric conversion element and a photoelectric conversion element drive circuit are integrally attached to a first substrate and exposed portions of the photoelectric conversion element and the photoelectric conversion element drive circuit on the first substrate are molded to conceal the exposed portions, the molded portion being a guide support portion that positions one end of an optical signal transmission line that transmits an optical signal output from the photoelectric conversion element relative to the photoelectric conversion element, thereby making it possible to reduce the size of the optical transmission module that is placed at the tip of the insertion portion of an endoscope device and improve the stability of its manufacture.
Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments.

1 is an overall configuration diagram of a medical endoscope apparatus according to an embodiment of the endoscope apparatus of the present disclosure; 1 is a schematic diagram showing a system configuration of an endoscope apparatus according to an embodiment of the present invention. 1 is an overall configuration diagram of an embodiment of an optical transmission module configured by integrating an image sensor, a photoelectric conversion element drive circuit, and a photoelectric conversion element. FIG. 4 is an overall configuration diagram of an embodiment of an optical transmission module configured in advance by integrating a photoelectric conversion element drive circuit and a photoelectric conversion element in the optical transmission module shown in FIG. 3 . FIG. 5 is a diagram illustrating the configuration of the optical transmission module shown in FIG. 4. FIG. 5 is a diagram illustrating the configuration of an optical transmission module using the optical transmission module shown in FIG. 4 . FIG. 1 is an overall configuration diagram of an embodiment of an optical transmission module configured by previously integrating a photoelectric conversion element, a transimpedance amplifier, and a lightning arrester. FIG. 13 is a diagram illustrating the configuration of another embodiment of the optical transmission module. FIG. 13 is a diagram illustrating the configuration of still another embodiment of the optical transmission module. FIG. 11 is a configuration explanatory diagram of another embodiment of an optical transmission module including an optical receiving module.

The endoscopic device according to the present disclosure will be described below with reference to the drawings, taking a medical endoscopic device as an example. In the case of a medical endoscopic device, the object to be observed is, for example, the respiratory system, digestive system, etc. For this reason, in order to be minimally invasive, it is desirable to make as small as possible the shape and size of the optical transmission module that is incorporated inside the tip of the insertion section and forms the hard part at the tip of the insertion section in a medical endoscopic device.

The endoscopic device according to the present disclosure is not limited to a medical endoscopic device. The medical endoscopic device described in this disclosure is merely one embodiment of the endoscopic device according to the present disclosure, and does not refer to all examples of the endoscopic device according to the present disclosure. For example, other examples of endoscopic devices that a person skilled in the art could conceive of without special creation based on the examples of the medical endoscopic device described in this disclosure naturally fall within the technical scope of the endoscopic device according to the present disclosure.

Figure 1 is a diagram showing the overall configuration of a medical endoscope device according to one embodiment of the endoscope device disclosed herein.

Figure 2 is a schematic diagram showing the system configuration of the endoscope device of this embodiment.

As shown in FIG. 1, the endoscope device 1 of this embodiment includes a long, tubular insertion section 11 that is inserted into the subject, an operating section 12 that is disposed on the base end side of the insertion section 11, and a connecting flexible tube (universal cord) 13 that extends from the operating section 12.

The insertion section 11 is configured such that, from the tip side, a tip section 11a, a curved movable section 11b, and a flexible tube section 11c are connected in sequence, and the flexible tube section 11c is connected to a connecting section 12a of the operation section 12.

The operation unit 12 has an operation piece such as a knob that operates the bending movable portion 11b of the insertion unit 11, and performs various operations on each part of the endoscope device. For example, a bending operation mechanism inside the operation unit can be operated in response to the rotation of the knob, and the bending movable portion 11b of the insertion unit 11 can be bent and extended to a desired shape and held there.

The connecting flexible tube 13 connects the endoscope device 1 to the processor (signal processing device) 2, and is provided with a connector portion 13a that is detachable from the connector connection portion 2a provided on the processor 2.

The processor 2 has a light source device, a system controller, an image processing device, etc., and is equipped with a monitor 3 that displays an electronic image of the observation area. The light emitted from the light source device of the processor 2 enters one end of an LCB (Light Carrying Bundle) and propagates through the LCB to the other end by repeating total reflections within the LCB. Although not shown in FIG. 2, the LCB extends from the connector connection part 2a through the connecting flexible tube 13, the operation part 12, and the insertion part 11 to the tip part 11a of the insertion part 11.

An illumination window and an observation window (objective window) are formed at the tip 11a of the insertion section 11. Inside the tip 11a, a light distribution lens is provided facing the illumination window and into which the light emitted from the exit end of the LCB is incident. The light emitted from the exit end of the LCB is irradiated from the illumination window via the light distribution lens to the observation location inside the subject. In addition, an objective lens is provided facing the observation window (objective window) to receive return light from the observation location inside the subject (the portion irradiated by the light emitted from the illumination window).

Inside the tip 11a of the insertion section 11 are an image sensor that accumulates the optical image (return light from the observation location) formed at each pixel on the light receiving surface via the objective lens as an electric charge according to the amount of light, and generates and outputs R, G, and B pixel signals, and a driver and processing circuit that drives and controls the image sensor to read and output one field or one frame of pixel signals as a video signal of the observation location at a predetermined time interval (for example, 1/60 second or 1/30 second interval). The image sensor and driver and signal processing circuit are integrated into an integrated circuit, and hereinafter the image sensor and driver and signal processing circuit are collectively referred to as the image sensor 21. For example, a CCD image sensor or a CMOS image sensor is used as the image sensor 21.

Furthermore, as shown in FIG. 2, inside the tip 11a of the insertion section 11, there are provided a photoelectric conversion element 23 that converts the video signal, which is an electrical signal, into an optical signal output in order to optically transmit and output the video signal output from the image sensor 21 toward the processor 2, and a photoelectric conversion element drive circuit 22 that drives the photoelectric conversion element 23 in response to the video signal output from the image sensor 21. The photoelectric conversion element 23 is, for example, a light-emitting diode, a semiconductor laser, etc., and in this embodiment, a vertical cavity surface emitting laser (VCSEL, Vertical Cavity Surface Emitting LASER) is used. The photoelectric conversion element drive circuit 22 is, for example, composed of a photoelectric conversion element drive IC, and in this embodiment, a VCSEL drive IC is used.

Various signal lines, an LCB, a drive power supply line, etc. are inserted inside the connecting flexible tube 13. The various signal lines include, for example, a control signal line 31 that transmits control signals for the image sensor 21 and the VCSEL drive IC (photoelectric conversion element drive circuit) 22 from the processor 2 to the endoscope device 1, a video signal transmission line 32 that transmits a video signal of the observation location that is converted into an optical signal and output from the vertical cavity surface emitting laser (photoelectric conversion element) 23 from the endoscope device 1 to the processor 2, and a switch signal line 33 that transmits an operation signal of a switch provided in the operation unit 12 of the endoscope device 1 to the processor 2.

Of these, the control signal line 31 and the video signal transmission line 32, together with the drive power supply line 34 that supplies drive power to the image sensor 21 and the VCSEL drive IC 22 provided in the tip 11a of the insertion section 11, extend from the connector section 13a through the connecting flexible tube 13 and the operation section 12 to the insertion section 11, just like the LCB, and reach the tip 11a inside the insertion section 11. The control signal line 31 and the drive power supply line 34 are made of metal cables (electrical wires), and the video signal transmission line 32 is made of optical fiber cable.

The connector section 13a of the connecting flexible tube 13 includes a photoelectric conversion element 26, a signal conversion circuit section 27, and a protection circuit section 28, as shown in FIG. 2, in order to convert the video signal transmitted as an optical signal via the video signal transmission line 32 back into an electrical signal and then supply it to the processor 2.

The photoelectric conversion element 26 converts the video signal transmitted as an optical signal via the video signal transmission line 32 into an electrical signal consisting of a current signal output and outputs it. The photoelectric conversion element 26 is, for example, a photodiode, a phototransistor, etc., and in this embodiment, a photodiode is used.

The signal conversion circuit unit 27 performs impedance conversion on the current signal output of the photodiode (photoelectric conversion element) 26 corresponding to the video signal, amplifies it, and outputs it as a voltage signal. In this embodiment, a transimpedance amplifier (TI) 27 is used as the signal conversion circuit unit.

The protection circuit unit 28 protects, for example, the control board 41 provided in the processor 2 from an abnormally high voltage that occurs transiently on the circuit side of the endoscope device 1. In this embodiment, a lightning arrester (LA) 28 is used as the protection circuit unit.

The output of the lightning arrester 28 (voltage signal output of the video signal) is connected to the corresponding connection pins of the board-to-board connector (B to B Connector) 29 provided in the connector section 13a, together with the inputs/outputs of the control signal line 31, the switch signal line 33, and the drive power supply line 34, each made of a metal cable.

When the connector portion 13a of the connecting flexible tube 13 is connected to the connector connection portion 2a of the processor 2, the board-to-board connection connector (endoscope device connector) 85 of the connector portion 13a is coupled to the board-to-board connection connector (processor connector) 95 provided on the control board 90 of the processor 2, and the control signal line 31, video signal transmission line 32, switch signal line 33, and drive power supply line 34 of the endoscope device 1 are connected to the corresponding outputs/inputs on the control board 41 side of the processor 2.

The processor 2 comprehensively controls the entire endoscope system consisting of the endoscope device 1, the processor 2, and the monitor 3 by executing various programs stored in the memory by the system controller provided on the control board 41. For example, the processor 2 drives and controls corresponding devices on the processor 2 side based on switch operation signals received from the endoscope device 1 via the switch signal line 33, and drives and controls the image sensor 21 and the VCSEL driving IC 22 on the endoscope device 1 side based on control signals transmitted via the control signal line 31. The processor 2 also displays an electronic image of the observation area on the monitor 3 based on the video (image) signal received via the video signal transmission line 32, and records it on an image recording medium.

In the endoscope device 1 according to the present embodiment, the image sensor 21, VCSEL driving IC (photoelectric conversion element driving circuit) 22, and vertical cavity surface emitting laser (photoelectric conversion element) 23 provided inside the tip 11a of the insertion section 11 are integrated in advance as an optical transmission module 20, and can be integrally attached inside the tip 11a. In addition, the photodiode (photoelectric conversion element) 26, transimpedance amplifier 27, and lightning arrester 28 provided inside the connector section 13a of the connecting flexible tube 13 are also integrated in advance as an optical transmission module 25, and can be integrally attached inside the connector section 13a. Next, examples of the optical transmission modules 20 and 25 will be described with reference to the drawings.

Figure 3 is an overall configuration diagram of one embodiment of an optical transmission module that integrates an image sensor, a photoelectric conversion element drive circuit, and a photoelectric conversion element.

Figure 4 is an overall configuration diagram of one embodiment of an optical transmission module in which the photoelectric conversion element drive circuit and the photoelectric conversion element are pre-integrated in the optical transmission module shown in Figure 3.

Figure 5 is an explanatory diagram of the configuration of the optical transmission module shown in Figure 4.

Figure 6 is an explanatory diagram of the configuration of an optical transmission module using the optical transmission module shown in Figure 4.

As shown in FIG. 3, the optical transmission module 20 of this embodiment is configured to include an image sensor 21, a VCSEL driving IC 22, and a vertical cavity surface emitting laser 23. Of these, the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 are integrated in advance as an optical transmission module 50 as shown in FIG. 4. The optical transmission module 50 functions as an electrical signal/optical signal conversion unit that converts an electrical signal into an optical signal.

In the illustrated example, the VCSEL driver IC 22 and the vertical cavity surface emitting laser 23 are configured as, for example, SMDs (surface mounted devices) and are attached and fixed to the optical transmission module substrate 51, which serves as the first substrate of the optical transmission module 20.

The optical transmission module board 51 is composed of an L-shaped curved printed wiring board (PWB) with a mounted board section 51x and a non-mounted board section 51z, as shown in FIG. 5(A), for example. Although not shown in FIG. 5(A), component connection terminal sections and signal/power connection terminal sections are pre-formed at predetermined positions on the board of the optical transmission module board 51, and board circuits that connect these component connection terminal sections and signal/power connection terminal sections are formed on the board surface or inside the board.

The component connection terminal section determines the placement positions of the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 on the board of the optical transmission module board 51. The signal/power connection terminal section determines the connection positions, on the board of the optical transmission module board 51, to the board circuit of the video signal output from the image sensor 21, the control signal supplied from the processor 2 via the control signal line 31, and the drive power supplied via the drive power supply line 34.

In the illustrated example, the component connection terminal portion is formed on the inner board surface 51xi of the mounting board portion 51x of the L-shaped optical transmission module board 51. In contrast, the signal/power connection terminal portion is formed on the outer board surface 51zo of the non-mounting board portion 51z of the L-shaped optical transmission module board 51.

As shown in FIG. 5(B), the optical transmission module 50 is configured by attaching and fixing the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 to corresponding mounting positions on the board surface 51xi of the L-shaped optical transmission module board 51 on which the component connection terminal portion is formed. At this time, each terminal of the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 is connected to the corresponding terminal of the component connection terminal portion. As a result, the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 are connected to corresponding terminals of the signal/power connection terminal portion formed on the non-mounted board portion 51z of the optical transmission module board 51 via the board surface of the optical transmission module board 51 or the board circuit inside the board.

In the illustrated example, the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 are provided on the inner substrate surface 51xi of the L-shaped optical transmission module substrate 51, but the VCSEL driving IC 22 may be provided on the inner substrate surface 51zi of the non-mounted substrate portion 51z of the L-shaped optical transmission module substrate 51.

As a result, the optical transmission module 50 is configured such that the light emission direction (+z direction on the z-axis) of the light-emitting surface of the vertical cavity surface-emitting laser 23 does not intersect with the non-mounted substrate portion 51z of the L-shaped optical transmission module substrate 51 on which the signal/power connection terminal portion is provided. Then, when the vertical cavity surface-emitting laser 23 is mounted on the L-shaped optical transmission module substrate 51, the light emission direction side (+z direction on the z-axis) of the light-emitting surface is open. In addition, the optical transmission module 50 has a substrate surface structure without irregularities that is suitable for connection to other substrates, since the VCSEL driving IC 22 and the vertical cavity surface-emitting laser 23 are not mounted on the substrate surface 51zo on the outer side of the non-mounted substrate portion 51z on which the signal/power connection terminal portion is formed, and the mounted components do not get in the way.

In the optical transmission module 50, with the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 fixed, the inner board surface 51xi of the optical transmission module board 51 is sealed with the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 together with the molded part 52 by a predetermined thickness (length along the z-axis direction) L along the direction in which the board surface 51xi faces (z-axis direction) as shown in FIG. 5(C).

The molded part 52 is made of, for example, a sealing resin formed by injection molding. Usually, a resin having functionality such as adhesion to chips and substrates, heat resistance, heat dissipation, thermal expansion coefficient, and mechanical strength is used for the sealing resin, for example, a thermosetting epoxy resin mixed with silica SiO _2. In this embodiment, for example, a heat dissipation resin having excellent heat dissipation function and electrical insulation function is used so that the heat generated by the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 can be diffused. Note that the molded part 52 is not limited to the above-mentioned configuration using the heat dissipation resin, and can also be configured using a metal, a heat conductive sheet, or the like.

When molding the molded section 52, an optical fiber holding hole 53 is formed in the molded section 52. The optical fiber holding hole 53 is a through hole that penetrates the molded section 52, and has a hole opening that faces the light emitting surface of the vertical cavity surface emitting laser 23. With the substrate surface 51xi sealed, the optical fiber holding hole 53 is designed so that its hole axis extends in the light emission direction from the light emitting surface of the vertical cavity surface emitting laser 23, i.e., in the optical axis direction of the laser light (the direction along the z-axis in the figure).

As a result, the optical fiber holding hole 53 functions as a ferrule that holds the fiber end face of the optical fiber 36 that constitutes the video signal transmission line (optical fiber cable) 32 in a state of being centered with respect to the light-emitting surface of the vertical cavity surface-emitting laser 23. On the insertion section 11 side of the video signal transmission line 32, the optical fiber 36 is inserted into the optical fiber holding hole 53 and held in the optical fiber holding hole 53 with the tip fiber end face in close contact with the light-emitting surface of the vertical cavity surface-emitting laser 23.

The optical fiber 36 extends from the optical transmission module 50 through the insertion section 11, the operation section 12, and the connecting flexible tube 13, and its base end is connected to the connector section 13a of the connecting flexible tube 13, forming a video signal transmission line 32 that transmits the video signal of the image sensor 21 to the processor 2 as an optical signal.

As shown in FIG. 6, the optical transmission module 20 is configured by integrally assembling an image sensor 21, an optical transmission module 50 including a VCSEL driving IC 22 and a vertical cavity surface emitting laser 23, and an optical transmission module substrate 61 serving as a second substrate of the optical transmission module 20.

For example, the optical transmission module board 61 is composed of a substantially T-shaped curved printed wiring board (PWB) having a sensor mounting board section 61x and a module mounting board section 61z protruding from the board surface 61xi on the inner side of the sensor mounting board section 61x, as shown in FIG. 6(A).

Although not shown in FIG. 6(A), an image sensor connection terminal section, an optical transmission module connection terminal section, and a signal/power supply connection terminal section are formed at predetermined positions on the board of the optical transmission module board 61. In addition, on the board surface or inside the board of the optical transmission module board 61, a board circuit is formed that connects the terminals of these image sensor connection terminal section and optical transmission module connection terminal section, and connects these image sensor connection terminal section and optical transmission module connection terminal section to the signal/power supply line connection terminal section.

The image sensor connection terminal section determines the position of the image sensor 21 on the optical transmission module board 61. The optical transmission module connection terminal section determines the position of the optical transmission module 50, which is formed by integrating the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23, on the optical transmission module board 61. The signal/power line connection terminal section determines the connection positions of the control signal line 31 and the drive power supply line 34, which are extended from the processor 2 to the insertion section 11, to the optical transmission module board 61 on the optical transmission module board 61.

In the illustrated example, the image sensor connection terminal portion is formed on the outer board surface 61xo of the sensor mounting board portion 61x of the T-shaped optical transmission module board 61. The optical transmission module connection terminal portion is formed on the inner board surface 61zi of the module mounting board portion 61z of the T-shaped optical transmission module board 61. The signal/power line connection terminal portion is formed on the outer board surface 61zo of the module mounting board portion 61z of the T-shaped optical transmission module board 61, on the side opposite (back side) to the board surface 61zi.

The optical transmission module board 61 has been described as a T-shaped printed wiring board, but the T-shape does not need to be limited to the position where the module mounting board part 61z protrudes from the sensor mounting board part 61x at the center of the length of the inner board surface 61xi of the sensor mounting board part 61x, and may be biased toward either end in the length direction, as in the illustrated example. In addition, the printed wiring board constituting the optical transmission module board 61 may be L-shaped, with the module mounting board part 61z protruding from either end in the length direction of the inner board surface 61xi of the sensor mounting board part 61x.

As shown in FIG. 6B, the optical transmission module 20 has an image sensor 21 configured as an SMD (surface mount device) or a through-hole mount device (insertion mount device) attached and fixed to the outer board surface 61xo of the sensor mounting board portion 61x on which the image sensor connection terminal portion of the optical transmission module board 61 is formed. At this time, each terminal of the image sensor connection terminal portion provided on the outer board surface 61xo of the optical transmission module board 61 is connected to each corresponding terminal of the image sensor 21, and the image sensor 21 is connected to a board circuit provided on the board surface or inside the board of the optical transmission module board 61. The image sensor 21 is connected to the corresponding terminals of the optical transmission module connection terminal portion and the signal/power supply connection terminal portion formed on the module mounting board portion 61z of the optical transmission module board 61 via this board circuit.

The shape and size (area) of the board surface of the sensor mounting board portion 61x of the optical transmission module board 61 is approximately equal to or smaller than that of the image sensor 21. As a result, when the optical transmission module 20 is viewed from the image sensor 21 side (when viewed in the +z direction in FIG. 6), the optical transmission module board 61 does not protrude from the outer edge of the housing of the image sensor 21. The image sensor 21 is configured, for example, with a flip chip structure or a package structure with exposed terminals such as BGA (ball grid array) or QFP (quad flat package), and the optical transmission module board 61 has a shape and size that does not protrude from the outer edge of the housing of the image sensor 21.

In the example shown in FIG. 6(B), the optical transmission module 20 is configured by attaching and fixing an optical transmission module 50 equipped with a VCSEL driving IC 22 and a vertical cavity surface emitting laser 23 to the board surface 61zi of the module mounting board portion 61z, on which the optical transmission module connection terminal portion of the optical transmission module board 61 is formed, by bonding mounting using solder balls on a bump material. At this time, each terminal of the signal/power connection terminal portion formed on the board surface 51zo on the outer side of the non-mounting board portion 51z of the optical transmission module board 51 is connected directly or indirectly via a board circuit to the corresponding terminals of the image sensor connection terminal portion and the signal/power connection terminal portion formed on the board surfaces 61xo and 61zi of the optical transmission module board 61.

The mounting position of the optical transmission module 50 on the inner board surface 61zi of the module mounting board section 61z in the optical transmission module board 61 is set in advance by the arrangement position of the optical transmission module connection terminal section so that the outer board surface 51xo of the mounting board section 51x in the optical transmission module board 51 of the optical transmission module 50 does not directly abut the inner board surface 61xi of the sensor mounting board section 61x in the optical transmission module board 61 on which the image sensor 21 is mounted, as shown in FIG. 6(B). As a result, in the optical transmission module 20, when the image sensor 21 and the optical transmission module 50 are mounted on the optical transmission module board 61, the image sensor 21 does not directly face and does not abut on the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 of the optical transmission module 50. As a result, a separation space S is formed between the two board sections 51x and 61x.

In this embodiment, as shown in FIG. 6C, the optical transmission module 20 is configured such that the separation space S is filled with a sealing resin and a molded section 62 is provided. In the illustrated example, the molded section 62 is in contact with the sensor rear section (substrate surface 61xi) of the optical transmission module substrate 61 on which the image sensor 21, which serves as a heat source, is mounted, and the photoelectric conversion element rear section (substrate surface 51xo) of the optical transmission module substrate 51 on which the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23, which also serve as heat sources, are mounted, so as to cover them. As a result, the heat from these heat sources is absorbed by the molded section 62 more quickly than when the molded section 62 is not provided in the separation space S between the opposing sensor rear section (substrate surface 61xi) and the photoelectric conversion element rear section (substrate surface 51xo). The heat transferred to the molded portion 62 from these heat-generating components, including the image sensor 21, is dissipated outside the separation space S from the opposing sensor rear portion (substrate surface 61xi) and the peripheral surface of the molded portion 62 that is not in contact with the sensor rear portion (substrate surface 61xi), facilitating the dissipation of heat from these heat-generating components.

In addition, in this embodiment, the size (area) of the mounting board section 51x of the optical transmission module board 51 when the optical transmission module 50 is viewed from the image sensor 21 side is equal to or smaller than the size (area) of the sensor mounting board section 61x of the optical transmission module board 61. In the illustrated example, since the size of the mounting board section 51x is smaller than the size of the sensor mounting board section 61x, the mold section 62 is configured to surround the periphery of the mold section 52 of the optical transmission module 50. Even in this case, when the optical transmission module 20 is viewed from the image sensor 21 side, the mold section 62 has a shape and size that does not protrude from the outer edge of the housing of the image sensor 21.

The molded part 62 is made of a sealing resin formed by injection molding, for example, like the molded part 52. Usually, the sealing resin is made of a resin having functionality such as adhesion to chips and substrates, heat resistance, heat dissipation, thermal expansion coefficient, and mechanical strength, for example, by mixing silica SiO ₂ into a thermosetting epoxy resin. In this embodiment, for example, a heat dissipation resin having excellent heat dissipation function and electrical insulation function is used so that heat from heat generating components such as the image sensor 21 can be diffused. The molded part 62 is not limited to the above-mentioned heat dissipation resin, and can also be made of a metal, a heat conductive sheet, or the like.

The optical transmission module 20, in which the image sensor 21 and the optical transmission module 50 are integrally assembled to the optical transmission module substrate 61 and the molded portion 62 is formed in the separation space portion S, is held by inserting the optical fiber 36 of the video signal transmission line 32 (optical fiber cable) that transmits the video signal from the image sensor 21 to the processor 2 into the optical fiber holding hole 53 of the optical transmission module 50 as shown in FIG. 6(C). In addition, the control signal line 31 that transmits control signals for the image sensor 21 and the VCSEL driving IC 22 from the processor 2 to the endoscope device 1, and the driving power supply line 34 that supplies driving power from the processor 2 to the image sensor 21, the VCSEL driving IC 22, etc. are wired and connected to the signal/power connection terminal portion formed on the outer substrate surface 61zi of the optical transmission module substrate 61.

Even in this case, the optical transmission module 20 shown in the figure has the sensor mounting board section 61x and the module mounting board section 61z of the optical transmission module board 61 bent and arranged in an approximately T-shape, so that when the optical transmission module 20 is viewed from the image sensor 21 side, the connection sections of the control signal line 31 and the drive power supply line 34 to the signal/power connection terminal section formed on the board surface 61zi are also shaped so as not to protrude from the outer edge of the housing of the image sensor 21, just like the optical fiber 36 of the video signal transmission line 32 attached to the optical transmission module 50.

The optical transmission module 20, to which the video signal transmission line 32, the control signal line 31, and the drive power supply line 34 are wired, is housed and fixed inside the tip 11a of the insertion section 11, with the imaging surface of the imaging element of the image sensor 21 facing the exit side of the objective lens that receives the return light from the observation location inside the subject (the portion irradiated by the light from the illumination window).

According to the endoscope device 1 equipped with such an optical transmission module 20, when the optical transmission module 20 is housed inside the tip 11a of the insertion section 11, the optical transmission module 50 is configured such that the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 mounted on the substrate surface 51xi of the optical transmission module substrate 51 are sealed in a molded section 52 having an optical fiber holding hole 53.

As a result, in the optical transmission module 50, the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 are covered by the molded part 52, so that external forces do not directly act on the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23, and the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 can be protected, facilitating the automatic assembly work of the optical transmission module 50 to the optical transmission module board 61. Also, the occurrence of failures in the optical transmission module 50 due to the adhesion of dust and the like to the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 can be prevented.

The molded section 52 is made of a resin with excellent heat dissipation properties, so it can dissipate heat from the heat-generating components, the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23, and the heat dissipation area of each of the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 can be expanded from the surface area of each chip housing to the surface area of the molded section 52, improving the heat dissipation performance of the optical transmission module 50.

Furthermore, the optical transmission module 50 has an optical fiber holding hole 53 in the molded section 52, and the molded section 52 also functions as a ferrule that keeps the end faces of the optical fiber 36 and the light-emitting surface of the vertical cavity surface-emitting laser 23 aligned with each other.

As a result, with the optical fiber 36 of the video signal transmission line 32 attached to the optical fiber holding hole 53, the optical transmission module 50 can be arranged so that the protective portion of the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 and the ferrule portion for the optical fiber 36 overlap along the light emission direction from the light emitting surface of the vertical cavity surface emitting laser 23 (the +z direction on the z axis).

As a result, the optical transmission module 50 can reduce the dimensions along the light emission direction (+z direction on the z-axis) of the optical transmission module 50 while protecting the VCSEL driving IC 22 and vertical cavity surface emitting laser 23 mounted on the substrate surface 51xi by using the molded part 52 that functions as a ferrule for the optical fiber 36, thereby making it possible to reduce the overall size of the optical transmission module 50.

In line with the miniaturization of the optical transmission module 50 itself, the optical transmission module 20 can separate the image sensor 21, which is a heat-generating component, from the VCSEL driving IC 22 and vertical cavity surface-emitting laser 23 of the optical transmission module 50, which are also heat-generating components, by providing a separation space S, and can arrange the orientations of the two components so that they do not face each other, facing in opposite directions (opposite directions in the ±z directions on the z axis). The periphery of the optical transmission module 50, including the separation space S, can then be covered with a molded section 62 made of resin with excellent heat dissipation properties.

As a result, the molded part 62 can protect the dimensional length of the optical transmission module 20, including the optical transmission module 50, along the light emission direction (+z direction on the z-axis) from the light emitting surface of the vertical cavity surface emitting laser 23 from external forces, and the heat dissipation area of the image sensor 21, which is a heat generating component, and the VCSEL driving IC 22 of the optical transmission module 50 can be increased by the surface integral of the molded part 62.

In addition, when the optical transmission module 20 is viewed from the image sensor 21 side, the molded section 62 and the connection parts of the control signal line 31 and the drive power supply line 34 do not protrude from the outer edge of the housing of the image sensor 21. Therefore, when assembling the optical transmission module 20 inside the tip 11a of the insertion section 11, the molded section 62 acts as a guide, making the assembly work easier.

The molded part 62 is in contact with and covers the sensor rear part (substrate surface 61xi) of the optical transmission module substrate 61 on which the image sensor 21, which serves as a heat source, is mounted, and the photoelectric conversion element rear part (substrate surface 51xo) of the optical transmission module substrate 51 on which the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23, which also serve as heat sources, are mounted. As a result, heat from these heat sources is absorbed by the molded part 62 more quickly than when the molded part 62 is not provided in the separation space S, and the heat is dissipated outside the separation space S from the opposing sensor rear part (substrate surface 61xi) and the peripheral surface of the molded part 62 that is not in contact with the sensor rear part (substrate surface 61xi), thereby facilitating the dissipation of heat from these heat-generating components.

Furthermore, when the optical transmission module 20 is housed and placed in the tip 11a of the insertion section 11, the outer peripheral surface of the molded section 62, which also serves as a guide during assembly, is in contact with the inside of the housing of the tip 11a of the insertion section 11, so that heat dissipation from the image sensor 21 and the VCSEL driving IC 22 and vertical cavity surface emitting laser 23 of the optical transmission module 50 can be diffused throughout the entire insertion section 11, including the curved movable section 11b and flexible tube section 11c, which are larger than the surface area of the chip housing of the image sensor 21 and the VCSEL driving IC 22.

Therefore, the optical transmission module 20 according to this embodiment, which includes an image sensor 21 and an optical transmission module 50 including a VCSEL driving IC 22 and a vertical cavity surface emitting laser 23, can reduce the size of the optical transmission module 20 itself, and can minimize the outer diameter and length of the tip 11a of the insertion section 11, into which the optical transmission module 20 is incorporated and which becomes a hard part (non-flexible/extendable part), making the insertion section 11 of the endoscope device 1 less invasive.

In addition, even if the outer diameter and length of the tip 11a of the insertion part 11 are reduced, the optical transmission module 20 equipped with the image sensor 21, VCSEL driving IC 22, and vertical cavity surface emitting laser 23 can be stably operated due to the improved heat dissipation performance.

In addition, the optical transmission module 20 is configured by assembling a fiber section consisting of an optical transmission module 50 to which the optical fiber 36 of the video signal transmission line 32 is connected and fixed, and a PD (Power Delivery) section consisting of an optical transmission module board 61 equipped with an image sensor 21 to which metal cables such as the control signal line 31 and the drive power supply line 34 are connected and fixed. This means that the fiber section and the PD (Power Delivery) section can be manufactured independently and separately, improving the manufacturability of the optical transmission module 20.

Next, an embodiment of the optical transmission module 25 provided inside the connector portion 13a of the connecting flexible tube 13 will be described with reference to the drawings.

Figure 7 is a diagram illustrating the configuration of one embodiment of an optical transmission module that is configured by previously integrating a photoelectric conversion element, a transimpedance amplifier, and a lightning arrester.

As shown in FIG. 7, the optical transmission module 25 of this embodiment is configured to include a photodiode (photoelectric conversion element) 26, a transimpedance amplifier (signal conversion circuit section) 27, a lightning arrester (protection circuit section) 28, and an endoscope device connector 85. Among these, the photodiode 26, the transimpedance amplifier 27, and the lightning arrester 28 are configured as a pre-integrated optical receiving module 70. The optical receiving module 70 functions as an optical signal/electrical signal conversion section that converts an optical signal into an electrical signal.

In the illustrated example, the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 are configured as SMDs (surface mounted devices) and are attached and fixed to the optical receiving module board 71, which serves as the first board of the optical transmission module 25, as shown in FIG. 7(A).

The optical receiver module board 71 is composed of, for example, a flat printed wiring board (PWB). Although not shown in the figure, component connection terminals and signal/power connection terminals are formed at predetermined positions on the board of the optical receiver module board 71, and a board circuit that connects these component connection terminals and signal/power connection terminals is formed on the board surface or inside the board.

The component connection terminal section determines the placement positions of the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 on the board of the optical receiver module board 71. The signal/power connection terminal section determines the output points on the board of the video signal supplied to the processor 2, and the input points on the board of the control signal and drive power supply supplied from the processor 2, in the board circuit of the optical receiver module board 71.

The component connection terminal portion is formed on the inner board surface 71xi of the flat optical receiver module substrate 71. In contrast, the signal/power connection terminal portion is formed on the outer board surface 71xo of the flat optical receiver module substrate 71, which is the side on which no components are mounted, in the illustrated example.

The optical receiving module 70 is configured by attaching and fixing a photodiode 26, a transimpedance amplifier 27, and a lightning arrester 28 to the board surface 71xi of the optical transmitting module board 71. The terminals of the photodiode 26, the transimpedance amplifier 27, and the lightning arrester 28 are connected to corresponding terminals of the corresponding component connection terminal parts. As a result, the photodiode 26, the transimpedance amplifier 27, and the lightning arrester 28 are connected via the board surface or the board circuit inside the board, and are also connected to corresponding terminals of the signal/power connection terminal parts formed on the board surface 71xo of the non-mounted board surface side 71.

An L-shaped bent terminal piece 74 is connected and fixed to each corresponding terminal of the signal/power connection terminal portion formed on the board surface 71xo. Each L-shaped bent terminal piece 74 has a board surface abutting piece 74x and a protruding piece 74z that protrudes perpendicularly from the board surface abutting piece 74x. Each L-shaped bent terminal piece 74 changes the facing direction of each terminal of the signal/power connection terminal portion formed on the board surface 71xo of the optical transmission module board 71 from a direction perpendicular to the board surface 71xo (+z direction on the z axis) to a parallel direction along the board surface 71xo (-x direction on the x axis).

Even if the photodiode 26 is mounted on the flat optical receiver module substrate 71 so that the light incidence direction is perpendicular to the substrate surface 71xi (-z direction on the z axis), the connection direction (mounting direction) of each L-shaped bent terminal piece 74 to other parts of the optical receiver module 70 is oriented in a direction (e.g., ±x direction on the x axis) different from the direction in which each terminal of the signal/power connection terminal part formed on the substrate surface 71xo faces (+z direction on the z axis).

In the optical receiving module 70, the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 are fixed, and the inner board surface 71xi of the optical receiving module board 71 is sealed together with the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 by a predetermined thickness L in the direction (z-axis direction) perpendicular to the board surface 71xi, as shown in FIG. 7(B).

The molded part 72 is made of, for example, a sealing resin formed by injection molding. Usually, a resin having functionality such as adhesion to chips and substrates, heat resistance, heat dissipation, thermal expansion coefficient, and mechanical strength is used for the sealing resin, for example, a thermosetting epoxy resin mixed with silica SiO _2. In this embodiment, for example, a heat dissipation resin having excellent heat dissipation function and electrical insulation function is used so that the heat generated by the photodiode 26 and the transimpedance amplifier 27 can be diffused. Note that the molded part 72 is not limited to the above-mentioned configuration using the heat dissipation resin, and can also be configured using metal, a heat conductive sheet, or the like.

In the illustrated example, the signal/power connection terminal portion is formed on the substrate surface 71xo of the optical receiving module substrate 71, but it may be formed on the substrate surface 71xi on which the component connection terminal portion is formed. In this case, as in the illustrated example, the L-shaped bent terminal piece 74 allows the connection direction (mounting direction) to other parts of the optical receiving module 70 to be a direction (for example, ±x direction on the x-axis) different from the direction in which each terminal of the signal/power connection terminal portion formed on the substrate surface 71xo faces (+z direction on the z-axis). Furthermore, in this case, the connection points between each terminal of the signal/power connection terminal portion on the substrate surface 71xi and each L-shaped bent terminal piece 74 can also be sealed and protected by the molded portion 72.

When the molded section 72 is formed on the inner substrate surface 71xi of the optical receiving module substrate 71, an optical fiber holding hole 73 is formed in the molded section 72. The optical fiber holding hole 73 is a through hole that penetrates the molded section 72 and has an opening that faces the light receiving surface of the photodiode 26. The optical fiber holding hole 73 is designed so that its hole axis extends in the same direction as the light incident direction of the light receiving surface of the photodiode 26, i.e., the optical axis direction of the received laser light (the direction along the z-axis in the figure).

As a result, the optical fiber holding hole 73 functions as a ferrule that holds the fiber end face of the optical fiber 36 that constitutes the video signal transmission line (optical fiber cable) 32 and the light receiving surface of the photodiode 26 in a centered state. The operating section 12 side of the optical fiber 36 is inserted into the optical fiber holding hole 73 from the hole opening, and is held in the optical fiber holding hole 73 with the fiber end face in close contact with the light receiving surface of the photodiode 26.

As shown in FIG. 7(C), the optical transmission module 25 is configured such that an optical receiving module 70 including a photodiode 26, a transimpedance amplifier 27, and a lightning arrester 28, and an endoscope device connector 85 of the endoscope device 1 used for board-to-board connection with a control board 90 on the processor 2 side are integrally assembled to an optical transmission module board 81 serving as a second board of the optical transmission module 25. In the illustrated example, the optical transmission module board 81 is configured from a flat printed wiring board (PWB).

Although not shown in FIG. 7(C), an optical receiving module connection terminal portion, a connector connection terminal portion, and a signal/power line connection terminal portion are formed at predetermined positions on the board of the optical transmission module board 81. In addition, on the board surface or inside the board of the optical transmission module board 81, a board circuit connected to these optical receiving module connection terminal portion, connector connection terminal portion, and signal/power line connection terminal portion is formed.

The optical receiver module connection terminal section determines the position on the board of the optical transmission module board 81 of the optical receiver module 70, which is an integrated combination of the photodiode 26, transimpedance amplifier 27, and lightning arrester 28. The signal/power line connection terminal section determines the connection positions on the board of the optical transmission module board 81 of the control signal line 31 and the drive power supply line 34, which are extended to the insertion section 11 via the connecting flexible tube 13 and the operation section 12. The connector connection terminal section determines the position on the board of the optical transmission module board 81 of the endoscope device connector 85, which is used for board-to-board connection with the control board 90 on the processor 2 side.

In the illustrated example, the optical receiver module connection terminal portion is formed on the board surface 81xi on the inner side (front side) of the flat optical transmission module board 81. The signal/power line connection terminal portion and the connector connection terminal portion are formed side by side on the board surface 81xo on the outer side (back side) of the flat optical transmission module board 81 along the arrangement direction of the optical receiver module 70, i.e., the incident direction of light to the photodiode 26 (direction along the z axis in the figure). The signal/power line connection terminal portion is located further back (-z side on the z axis) of the optical transmission module board 81 than the connector connection terminal portion.

In the optical transmission module 25, an optical receiver module 70 including a photodiode 26, a transimpedance amplifier 27, and a lightning arrester 28 is attached and fixed to the inner board surface 81xi of the optical transmission module board 81 on which the optical receiver module connection terminal portion is formed. At this time, the protruding piece portion 74z of each bent terminal piece 74 provided on the optical receiver module 70 is respectively connected to the corresponding terminal of the optical receiver module connection terminal portion formed on the inner board surface 81xi of the optical transmission module board 81, and further connected via the board circuit to the corresponding terminals of the signal/power line connection terminal portion and the connector connection terminal portion formed on the outer board surface 81xo.

As shown in FIG. 7(C), the optical transmission module 25 is configured such that a control signal line 31 for transmitting a control signal from the processor 2 to the image sensor 21 and VCSEL driving IC 22 of the optical transmission module 20, a switch signal line 33 for transmitting an operation signal of a switch provided in the operation unit 12 to the processor 2, and a drive power supply line 34 for supplying drive power to the image sensor 21 and VCSEL driving IC 22 of the optical transmission module 20, etc. are each wired to the signal/power line connection terminal portion formed on the outer board surface 81xo of the optical transmission module board 81.

The optical transmission module 25 is configured such that an endoscope device connector 85 for board-to-board connection is attached and fixed to the outer board surface 81xo of the optical transmission module board 81. At this time, each terminal of the connector connection terminal portion formed on the outer board surface 81xo of the optical transmission module board 81 is connected to a corresponding connection pin of the endoscope device connector 85 for board-to-board connection.

When the connector portion 13a provided on the connecting flexible tube 13 of the endoscope device 1 is attached to the connector connection portion 2a of the processor 2, the endoscope device connector 85 of the optical transmission module 25 is connected to the processor connector 95 on the processor side provided on the control board 90 of the processor 2.

In an endoscope device 1 equipped with such an optical transmission module 25, when the optical transmission module 25 is housed inside the housing of the connector portion 13a of the connecting flexible tube 13, the optical receiving module 70 is configured such that the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 mounted on the board surface 71xi of the optical transmitting module board 71 are sealed in a molded portion 72 equipped with an optical fiber holding hole 53.

As a result, in the optical receiving module 70, the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 are covered by the molded portion 72, so that external forces do not act directly on them and the transimpedance amplifier 27 and lightning arrester 28 can be protected, facilitating the automatic assembly work of the optical receiving module 70 to the optical transmission module board 81. In addition, it is possible to prevent failure of the optical transmitting module 50 due to the adhesion of dust or the like to the photodiode 26, transimpedance amplifier 27, or lightning arrester 28.

The molded section 72 is made of a resin with excellent heat dissipation properties, so it can dissipate heat from the heat-generating components, the photodiode 26 and the transimpedance amplifier 27. This allows the heat dissipation area of each of the photodiode 26 and the transimpedance amplifier 27 to be expanded from the surface area of each chip housing to the surface area of the molded section 72, improving the heat dissipation performance of the optical receiver module 70.

Furthermore, the optical receiving module 70 has an optical fiber holding hole 73 in the molded section 72, and the molded section 72 also functions as a ferrule that keeps the end faces of the optical fiber 36 and the light-emitting surface of the vertical cavity surface-emitting laser 23 aligned with each other.

As a result, with the optical fiber 36 of the video signal transmission line 32 attached to the optical fiber holding hole 73, the optical receiving module 70 can be arranged so that the protective parts of the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 and the ferrule part for the optical fiber 36 overlap along the direction of light incidence on the light receiving surface of the photodiode 26 (the +z direction on the z axis).

As a result, the optical receiver module 70 can reduce the dimensions along the light incidence direction (+z direction on the z-axis) of the optical receiver module 70 while protecting the photodiode 26, transimpedance amplifier 27, and lightning arrester 28 mounted on the substrate surface 81xi by using the molded portion 72 that functions as a ferrule for the optical fiber 36, thereby enabling the overall size of the optical receiver module 70 to be reduced.

By miniaturizing the optical receiving module 70 itself, the dimensional length of the optical transmission module 25 along the direction of light incidence on the light receiving surface of the photodiode 26 (the +z direction on the z axis), including the optical receiving module 70, can be protected from external forces by the molded part 72, and the heat dissipation area of the photodiode 26 and transimpedance amplifier 27, which are heat-generating components, can be increased by the surface integral of the molded part 72.

The optical transmission module 25 includes an optical receiver module 70 having a photodiode 26, a transimpedance amplifier 27, and a lightning arrester 28 according to this embodiment, and an endoscope device connector 85. This allows the optical transmission module 25 itself to be made smaller, and the outer diameter and length of the connector portion 13a of the connecting flexible tube 13, into which the optical transmission module 25 is incorporated and which becomes the hard portion (non-flexible/extendable portion), can be made as small as possible, improving the ease of handling of the connecting flexible tube 13.

Even if the connector portion 13a of the connecting flexible tube 13 is small, the improved heat dissipation performance allows the optical transmission module 25, which is equipped with the photodiode 26, transimpedance amplifier 27, and lightning arrester 28, to operate stably.

In addition, the optical transmission module 25 is configured by assembling a fiber section consisting of an optical receiving module 70 to which the optical fiber 36 of the video signal transmission line 32 is connected and fixed, and a PD (Power Delivery) section consisting of an optical transmission module board 81 equipped with an endoscope device connector 85 to which metal cables such as the control signal line 31, the switch signal line 32, and the drive power supply line 34 are connected and fixed. This means that the fiber section and the PD (Power Delivery) section can be manufactured independently and separately, improving the manufacturability of the optical transmission module 25.

Figure 8 is an explanatory diagram of the configuration of another embodiment of an optical transmission module.

In the description of the optical transmission modules 50-1 to 50-3 shown in FIG. 8, components that are the same as or similar to those in the optical transmission module 50 shown in FIG. 4 are given the same reference numerals and detailed descriptions of their configurations are omitted.

Figure 8(A) is a diagram illustrating the configuration of another embodiment of an optical transmission module.

The optical transmission module 50-1 shown in FIG. 8(A) differs from the optical transmission module 50 shown in FIG. 4 in the configuration of the optical fiber holding hole 53 formed in the molded portion 52, and the optical fiber holding hole 53 further includes an engagement recess 55. The engagement recess 55 is recessed in a predetermined radial direction (the radial direction shown upward in the illustrated example) around the axis of the optical fiber holding hole 53 on the inner peripheral surface of the optical fiber holding hole 53 at a predetermined distance from the light emitting surface side of the vertical cavity surface emitting laser 23.

On the other hand, the optical fiber 36 inserted in the optical fiber holding hole 53 has an engagement retaining piece 37 protruding from its outer circumferential surface. The engagement retaining piece 37 is formed on the outer circumferential surface of the optical fiber 36 at a predetermined distance from the light-emitting surface of the vertical cavity surface-emitting laser 23, i.e., the fiber end surface, with the tip end surface of the fiber in close contact with the light-emitting surface of the vertical cavity surface-emitting laser 23, and can engage with the engagement recess 55 of the optical fiber holding hole 53. The engagement retaining piece 37 is, for example, configured with a spring at its base end portion, and the free end portion (tip portion) side is displaced around the base end portion and can tilt with respect to the outer circumferential surface of the optical fiber 36, so that the tip side portion can abut against and separate from the outer circumferential surface of the optical fiber 36. In the normal state, the engagement retaining piece 37 separates the free end portion (tip portion) side from the outer circumferential surface of the optical fiber 36, and the separation position is a position larger than the hole radius of the optical fiber holding hole 53 in the radial direction centered on the axis of the optical fiber 36.

The optical transmission module 50-1 of this embodiment is equipped with an optical fiber positioning and holding mechanism consisting of an engagement recess 55 with which the engagement holding piece 37 of the optical fiber 36 can engage, so that the optical fiber 36 can be reliably positioned and held in the inserted state in the optical fiber holding hole 53 with the fiber end face in close contact with the light emitting surface of the vertical cavity surface emitting laser 23. Therefore, according to the optical transmission module 50-1 of this embodiment, the performance of the optical signal transmission function between the fiber end face of the optical fiber 36 and the light emitting surface of the vertical cavity surface emitting laser 23 can be further stabilized. In addition, the strength of the attachment state when the optical fiber 36 is inserted into the optical fiber holding hole 53 is also increased by the elastic restoring force of the engagement holding piece 37, which has spring properties.

Figure 8(B) is a diagram illustrating the configuration of another embodiment of an optical transmission module.

The optical transmission module 50-2 shown in FIG. 8(B) is different from the optical transmission module 50-1 shown in FIG. 8(A) in that the engagement recess 55 of the optical fiber holding hole 53, which constitutes the optical fiber positioning and holding mechanism with which the engagement holding piece 37 of the optical fiber 36 can be engaged, is configured in an annular groove shape, and the molded part 52 is divided into two parts, upper and lower, in the illustrated example, into molded parts 52a and 52b, with the cross section taken along a plane including the hole axis of the optical fiber holding hole 53.

In the optical transmission module 50-2 shown in FIG. 8(B), the optical transmission module substrate 51 as the first substrate to which the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23 are attached and fixed is not an L-shaped bent printed wiring board as in the optical transmission module 50 shown in FIG. 4, but is configured as an assembly of the optical transmission module substrate 51 made of a flat printed wiring board and the L-shaped bent terminal pieces 54 connected to the corresponding terminals of the signal/power connection terminal part of the substrate surface 51xo, similar to the optical reception module substrate 71 and the bent terminal pieces 74 of the optical reception module 70 shown in FIG. 7. Furthermore, in the optical transmission module 50-2 shown in FIG. 8(B), unlike the optical reception module 70 shown in FIG. 7, the protruding piece part 54z protruding vertically from the substrate surface abutting piece part 54x of the bent terminal piece 54 is covered by the molded part 52, except for the surface connected to the optical transmission module connection terminal part of the optical transmission module substrate 61 as the second substrate.

In the optical transmission module 50-2 of this embodiment, the engagement recess 55 of the optical fiber holding hole 53 of the optical fiber positioning and holding mechanism is configured in an annular groove shape, so that the optical fiber 36 can be inserted into the optical fiber holding hole 53 and positioned and held in a state in which the fiber end face at the tip of the optical fiber 36 is in close contact with the light emitting surface of the vertical cavity surface emitting laser 23, regardless of the protruding position of the engagement holding piece 37 on the outer peripheral surface of the optical fiber 36. In addition, the molded part 52 is divided into the molded part 52a and the molded part 52b with the cross section taken along the plane including the hole axis of the optical fiber holding hole 53, so that the optical fiber holding hole 53 can be easily formed in the optical fiber holding hole 53.

In this case, the molded part 52 is formed by joining the molded part 52a and the molded part 52b, and the molded part 52 is joined and fixed to the optical transmission module substrate 51 so as to cover the VCSEL driving IC 22 and the vertical cavity surface emitting laser 23, with the optical fiber holding hole 53 aligned with the light emitting surface of the vertical cavity surface emitting laser 23 attached and fixed to the optical transmission module substrate 51.

In the optical transmission module 50-2 of this embodiment, the optical fiber 36 can be inserted into the optical fiber holding hole 53 regardless of the protruding position of the engagement retaining piece 37 on the outer peripheral surface of the optical fiber 36, and the molded part 52 is divided with the cross section taken along a plane including the hole axis of the optical fiber holding hole 53, further improving the manufacturability of the optical transmission module 50.

Even if the optical transmission module 50-2 of this embodiment uses a flat printed wiring board for the optical transmission module substrate 51 as the first substrate, the L-shaped bent terminal piece 54 attached and fixed to the optical transmission module substrate 51 is integrally covered and supported by the molded part 52, except for the surface that connects to the optical transmission module connection terminal portion of the optical transmission module substrate 61, so that the bent shape of the optical transmission module substrate 51 and the L-shaped bent terminal piece 54 during the manufacture of the optical transmission module is stable.

Figure 8(C) is a diagram illustrating the configuration of another embodiment of the optical transmission module.

The optical transmission module 50-3 shown in FIG. 8(C) is different from the optical transmission module 50-1 shown in FIG. 8(A) in that the optical fiber holding hole 53 is not formed directly in the molded portion 52, but is formed in an optical fiber insertion tube 56 made of a separate cylindrical member, and that a fiber support member 57 is arranged on the inner surface of the optical fiber insertion tube 56 instead of the engagement recess 55 as an optical fiber positioning and holding mechanism.

The fiber support member 57 is, for example, configured as an annular spring flexure ring 57 having a curved cross-sectional shape in which the central portion along the ring axis direction is more expandable and contractible in the ring radial direction than both ends along the ring axis direction, and is structured to allow the insertion of the optical fiber 36 and to hold the inserted optical fiber 36 in an attached state.

The optical transmission module 50-3 of this embodiment does not need to directly form the sliding surface of the optical fiber 36 with the molded section 52 when the optical fiber 36 is inserted, so it is possible to select a material for the optical fiber insertion tube 56 that emphasizes other performance aspects, such as the workability when inserting the optical fiber 36 and the protection performance of the optical fiber during or after the work, without particularly emphasizing the heat dissipation function aspect as with the molded section 52.

In addition, the optical transmission module 50-3 of this embodiment can be configured as an annular spring deflection ring 57 in the optical fiber insertion tube 56 without having to form the optical fiber positioning and holding mechanism directly in the molded section 52, improving the workability of molding the molded section 52 and inserting the optical fiber 36 into the optical fiber holding hole 53.

Figure 9 is a diagram illustrating the configuration of yet another embodiment of an optical transmission module.

In addition, in the description of the optical transmission module 50-4 shown in FIG. 9, components that are the same as or similar to those in the optical transmission module 50 shown in FIG. 4 are given the same reference numerals, and detailed descriptions of the configurations are omitted.

The optical transmission module 50-4 shown in FIG. 9 is different from the optical transmission module 50-1 shown in FIG. 8(A) in that the molded section 52 is further provided with, in addition to the optical fiber holding hole 53, a groove (recess) 58 and an internal chamber 59 that is connected to the outside via an opening 59a.

In the optical transmission module 50-4 of this embodiment, the heat dissipation area of the molded section 52 is enlarged by the inner wall surfaces of the inner chamber section 59, which is connected to the outside via the groove section 58 and the opening section 59a, and the heat dissipation performance of the molded section 52 is further improved. This allows the optical transmission module 20, which is equipped with the image sensor 21, the VCSEL driving IC 22, and the vertical cavity surface emitting laser 23, to be driven more stably.

Figure 10 is a diagram illustrating the configuration of another embodiment of an optical transmission module equipped with an optical receiving module.

In addition, in the description of the optical transmission module 25-1 shown in FIG. 10, components that are the same as or similar to those of the optical transmission module 25 equipped with the optical receiving module 70 shown in FIG. 7 are given the same reference numerals as the relevant parts, and detailed descriptions of the configurations are omitted.

The optical transmission module 25-1 shown in FIG. 10 differs from the configuration of the optical transmission module 25 equipped with the optical receiving module 70 shown in FIG. 7 in that the optical receiving module 70-1 is configured by previously integrating the photodiode (photoelectric conversion element) 26 and the transimpedance amplifier 27, the lightning arrester 28 is independently mounted on the optical transmission module board 81 like the optical receiving module 70-1, and the attachment/detachment direction of the endoscope device connector 85-1 of the optical transmission module 25-1, which is connected board-to-board to the processor connector 95 on the processor side provided on the control board 90 of the processor 2, is changed from the parallel direction (direction along the z-axis in the figure) along the board surface of the optical transmission module board 81 on which the endoscope device connector 85-1 is mounted to the direction perpendicular to the board surface of the optical transmission module board 81 (direction along the x-axis in the figure).

In relation to the difference in configuration between the two described above, in the optical transmission module 25-1, each bent terminal piece 74 of the optical receiving module 70-1 is connected to a corresponding terminal of the optical receiving module connection terminal portion of the optical transmission module board 81, and is connected to a corresponding terminal of the connector connection terminal portion of the optical transmission module board 81 via the board surface of the optical transmission module board 81 or the board circuit inside the board. The voltage signal output of the video signal from the transimpedance amplifier 27 is supplied to the lightning arrester 28 via the board circuit, and the output of this lightning arrester 28 is then supplied to the corresponding terminal of the connector connection terminal portion of the optical transmission module board 81 via the board circuit.

In the optical transmission module 25-1 of this embodiment, the optical receiving module 70-1 and the lightning arrester 28 are mounted independently of each other on the optical transmission module board 81, so that the replacement of the lightning arrester 28 can be performed separately from the replacement of the optical receiving module 70-1, thereby reducing maintenance costs.

As is clear from the above, according to the endoscope device 1 of the present disclosure, in the optical transmission module 20, 25, the heat-generating components such as the VCSEL driving IC (photoelectric conversion element driving circuit) 22 and the transimpedance amplifier (signal conversion circuit section) 27 mounted on the substrate 51, 71 are molded and concealed with a heat dissipation material, and the molded sections 52, 72 are integrally formed with an optical fiber holding hole (guide holding section) 53 that positions and holds the end of the optical fiber (optical signal transmission line) 36 that transmits the optical signal output from the vertical cavity surface emitting laser (photoelectric conversion element) 23 and the optical signal input to the photodiode (photoelectric conversion element) 26 relative to these photoelectric conversion elements 23, 26, and are configured as a sub-module consisting of the optical transmission module 50 and the optical receiving module 70. Therefore, it is possible to achieve both stable operation of these heat-generating components in the optical transmission module 20, 25 and miniaturization of the optical transmission module 20, 25, and thus improve the performance of the endoscope device 1.

The configuration of the endoscopic device according to the present disclosure having such technical features is not limited to the configuration of the above-mentioned embodiment, and various modifications are possible by appropriately combining the configurations of each part of the above-mentioned embodiment, or by replacing each part with a different configuration that can achieve a similar function.

1. Endoscope device,
2. Processor (signal processing device),
2a connector connection portion,
3 monitors,
11 Insertion part,
11a tip portion,
11b bending movable part,
11c flexible tube portion,
12 Operation unit,
12a connecting portion,
13 Connecting flexible tube (universal cord),
13a connector portion,
20 Optical transmission module,
21 image sensor,
22 VCSEL driving IC (photoelectric conversion element driving circuit),
23 Vertical cavity surface emitting laser (photoelectric conversion element),
25 Optical transmission module,
26 Photodiode (photoelectric conversion element),
27 Transimpedance amplifier (signal conversion circuit section),
28 Lightning arrester (protection circuit part),
31 control signal line,
32 video signal transmission line,
34 Drive power supply line,
36 optical fiber,
37 Engagement retaining piece,
50 Optical transmission module,
51 Optical transmission module board,
51x mounting board section,
51z Non-mounted board part,
52 mold part,
53 Optical fiber holding hole,
54 bent terminal piece,
55 engagement recess,
56 Optical fiber insertion tube,
57 spring flexure ring (fiber support member),
58 Groove portion,
59 Inner room,
61 Optical transmission module board,
61x Sensor mounting board,
61z Module mounting board section,
62 mold part,
70 Optical receiving module,
71 Optical receiving module board,
72 mold part,
73 Optical fiber holding hole,
74 bent terminal piece,
81 Optical transmission module board,
85 Endoscope device connector,
90 control board,
95 processor connector,
S Separation space section.

Claims (5)

an insertion section having an imaging device at a tip portion thereof for imaging the inside of the subject;
an operation unit connected to a base end of the insertion unit and configured to operate the insertion unit;
a connecting flexible tube portion having one end connected to the operation portion and the other end provided with a connection portion for connecting to a processor;
An endoscope apparatus having
an optical transmission module, comprising: a first substrate on which a photoelectric conversion element for converting an electrical signal into an optical signal and a photoelectric conversion element drive circuit for causing the electrical signal output of the imaging device to be output as an optical signal from the photoelectric conversion element are mounted; an exposed portion of the photoelectric conversion element and the photoelectric conversion element drive circuit is formed with a guide holder for positioning and holding one end of an optical signal transmission line for transmitting the optical signal output of the photoelectric conversion element with respect to the photoelectric conversion element; and the exposed portion is molded and concealed with a heat dissipation member;
an optical transmission module configured by attaching the optical transmission module to a second board on which the imaging device is attached;
Including,
The photoelectric conversion element, the photoelectric conversion element drive circuit unit, and the imaging device are integrally assembled inside the tip portion of the insertion portion by the optical transmission module.
Endoscopic device. A substrate portion on which the photoelectric conversion element is attached in the first substrate of the optical transmission module and a substrate portion on which the imaging device is attached in the second substrate of the optical transmission module are separated to form a space between the two substrate portions.
The endoscope apparatus according to claim 1 . The photoelectric conversion element is mounted on the substrate portion of the first substrate such that a mounting direction of the photoelectric conversion element and a mounting direction of the imaging device on the substrate portion of the second substrate are opposite to each other.
The endoscope apparatus according to claim 2 . The optical transmission module includes:
The space is molded with a heat dissipation material,
the heat dissipation member is in contact with the substrate portion of the first substrate and the substrate portion of the second substrate;
The endoscope apparatus according to claim 2 . an insertion section having an imaging device at a tip portion thereof for imaging the inside of the subject;
an operation unit connected to a base end of the insertion unit and configured to operate the insertion unit;
a connecting flexible tube portion having one end connected to the operation portion and the other end provided with a connection portion for connecting to a processor;
An endoscope apparatus having
an optical receiving module, comprising: a photoelectric conversion element for converting an optical signal into an electric signal; and a signal conversion circuit for converting a current signal output of the photoelectric conversion element into a voltage signal output, the photoelectric conversion element and an exposed portion of the signal conversion circuit being attached to a first substrate; a guide holding portion for positioning and holding the other end of an optical signal transmission line extending from the insertion portion through the connecting flexible tube portion with respect to the photoelectric conversion element, the guide holding portion being molded and concealed with a heat dissipation member;
an optical transmission module configured by mounting the optical receiving module on a second board on which a device connection connector for connecting a control board provided on the processor side and a signal and power supply is mounted;
Including,
the photoelectric conversion element, the signal conversion circuit unit, and the device connection connector are integrally assembled by the optical transmission module inside the connection portion of the connecting flexible tube section.
Endoscopic device.

Images