FR2783611A1 - VIDEO ENDOSCOPE - Google Patents

Abstract

The present invention relates mainly to an endoscope, in particular to a compact video endoscope for medical use, for example dental use. An endoscope according to the present invention comprises a light source (11) incorporated in the shooting rod. applies in particular to the visualization of objects that are difficult to access. The present invention applies mainly to medical imaging, in particular to dental endoscopy.

Description

VIDEO ENDOSCOPE

  The present invention relates mainly to an endoscope, in particular to a compact video endoscope for use

medical, for example dental.

  Endoscopes of known type comprise, on the one hand, a housing provided with a light source intended to illuminate the object to be viewed as well as electronics for shaping the video signal connected by a

  cable to a rod comprising a video sensor and its associated optics.

  The cable comprises on the one hand very long optical fibers, for example equal to 1.8 m, the electrical cables supplying the video sensor, cables for transmitting the control signals and cables connecting the output of the video sensor. at the entrance to the shaping equipment

of the signal.

  Endoscopes of known type have many drawbacks. First, the housing and cable are heavy and do not

  do not allow easy handling of the rod carrying the video sensor.

  On the other hand, endoscopes of known type have a consumption

  high electrical temperature and significant heating.

  In addition, the continuity of the light supply optical fibers to the end of the rod does not allow the change

  optics to adapt optimally to the objects to be viewed.

  It is therefore an object of the present invention

to offer a compact endoscope.

  It is also an object of the present invention to provide a

handy endoscope.

  It is also an object of the present invention to provide a

  endoscope with low power consumption.

  It is also an object of the present invention to provide a

  endoscope having a simple construction.

  It is also an object of the present invention to provide a

  modular endoscope allowing to modify the optics of shooting.

  It is also an object of the present invention to offer an endoscope capable of adapting to various means of viewing or

recording images.

  These objects are achieved by an endoscope according to the present invention comprising a light source incorporated in the cane of

shooting.

  The main object of the invention is an endoscope comprising a light source and a rod, at least the distal end of which is capable of penetrating a cavity comprising objects to be viewed, said rod comprising a video sensor, characterized in that the source light is incorporated into the rod carrying the video sensor. The invention also relates to an endoscope, characterized in that the rod comprises an electronic circuit for shaping the signal delivered by the video sensor so as to make it usable by a

  display, recording or processing device.

  The invention also relates to an endoscope, characterized in that the light source comprises at least one incandescent lamp situated between the distal and proximal ends of the cane and in that the cane comprises optical fibers for supplying light between the lamp and the distal end of the cane having a length of between 4 cm and 20 cm, preferably between 6 cm and 14 cm or

  more preferably between 8 cm and 12 cm.

  The invention also relates to an endoscope, characterized in that the lamp is a miniature incandescent lamp comprising a

front focusing lens.

  The invention also relates to an endoscope, characterized in that it comprises means for cooling the

  light source by forced air circulation.

  The invention also relates to an endoscope, characterized in that it comprises a video sensor, in particular of the coupling circuit type.

  of loads, located near the proximal end of the rod.

  The invention also relates to an endoscope, characterized in that the rod is separable to form a handle and an optical head resistant to high temperatures prevailing in an autoclave. The invention also relates to an endoscope, characterized in that it comprises a video sensor, preferably of the circuit type to

  load coupling, located near the distal end of the rod.

  The invention also relates to an endoscope, characterized in that it comprises a light source arranged at

  near the distal end of the cane.

  The invention also relates to an endoscope, characterized in that the light source has low heat dissipation. The invention also relates to an endoscope, characterized in that the light source comprises light-emitting diodes of primary colors, in particular diodes

red, green and blue.

  go The invention also relates to an endoscope, characterized in

  that said endoscope is a dental endoscope.

  The invention also relates to an endoscope, characterized in that said endoscope comprises a flexible rod with respect to

to its longitudinal axis.

  The invention will be better understood by means of the

  description below and attached figures given as

  nonlimiting examples and in which: - Figure 1 is a perspective view of the preferred embodiment of the endoscope according to the present invention disassembled; - Figure 2 is a similar view of a first alternative embodiment of the endoscope according to the present invention disassembled; - Figure 3 is a similar view of a second alternative embodiment of an endoscope according to the present invention; - Figure 4 is a similar view of a third alternative embodiment of an endoscope according to the present invention; - Figure 5 is a diagram of a first embodiment of the endoscope output signal interface according to the present invention; - Figure 6 is a diagram of a second embodiment of the endoscope output signal interface according to the present invention; - Figure 7 is a diagram of a third embodiment of the endoscope output signal interface according to the present invention; - Figure 8 is a diagram of a fourth embodiment of the endoscope output signal interface according to the present invention; - Figure 9 is a diagram of a fifth embodiment of the endoscope output signal interface according to the

present invention.

  In FIGS. 1 to 9, the same references have been used

  to designate the same elements.

  In Figure 1, we can see the preferred embodiment of an endoscope 1 according to the present invention comprising a rod composed of a handle 3 and an optical head 5 advantageously interchangeable. The rod 3 comprises on the one hand a video sensor 7, advantageously with semiconductors, preferably of the charge coupled circuit type (CCD in English terminology) associated with its signal shaping electronics 9, including examples of embodiment will be explained with reference to Figures 5 to 9 and a device

  lighting or light source 11.

  The handle 3 is also connected to a cable 13 providing the electrical supply, preferably low voltage and / or the output of the display video signal. As a variant, the handle 3 may include an autonomous electrical supply, for example by rechargeable batteries or accumulators. Likewise, the handle 7 may include means for transmitting the wireless signal, an example of which is illustrated in FIG. 9. In such a case, the handle 3, devoid of cable 13, is particularly handy. The handle 3 may further include control switches such as for example a switch

on / off (not shown).

  The light source 11 to be used depends on the desired light intensity, the optical losses in the illumination and

  l Acquisition of the image and the sensitivity of the sensor 7.

  The preferred example illustrated in FIG. 1 comprises two halogen incandescent focused lamps each having a

  power of 4 W and a diameter less than or equal to 3 mm.

  Advantageously, lamps sold under the name ORBITEC are used, comprising front light focusing lenses facilitating the penetration of light into the inlets 15 of two light guides 17, preferably with optical fibers. The optical fibers 17 have a length of between 4 cm and 20 cm, preferably between 6 cm and 14 cm, preferably between 8 cm and 12 cm, for example equal to 9, or 11 cm. The use of short optical fibers causes very low light losses compared to those caused in conventional endoscopes typically having optical fibers of 1.8 m in length. The lighting device 11 also comprises, advantageously, a cooling device provided with a turbine (not shown) for forced circulation of air 35 entering through slots 19 located on the proximal side of the handle and leaving through openings substantially circular 21 practiced in the optical head 5. However, other modes of cooling, such as for example cooling by radiation using a radiator, or by convection, do not leave the framework

of the present invention.

  The optical head 5 comprises on the one hand mechanical coupling means, such as for example a cylinder 23 forming a rear barrel of the optical system, complementary to a cylindrical opening 25 made in the handle 3 and a cylindrical hole 27 for receiving a pin 29 of the handle 3. A lens train 31 possibly supplemented by mirrors or prisms make it possible to form the image of a

  object to be displayed, for example teeth 33 on the video sensor 7.

  The optical fibers 17 provide the light produced by the light source 11 near the distal end of

  The endoscope to illuminate the object to be observed.

  The use of interchangeable optical heads makes it possible on the one hand to sterilize the optical head in an autoclave, this head being devoid of any temperature-sensitive component and, on the other hand, to change the head 5 for a particular use. For example, the head 5 illustrated, which is particularly well suited to dental endoscopy, can be replaced by a lens making it possible to take photos or film patients or by a head better suited to ENT use, in urology or endoscopy industrial. In addition, the interchangeable heads make it possible to reduce the number of references to maintain in the catalog for various types of endoscopes likely to be marketed. The handle 3 is substantially waterproof, which allows its disinfection by immersing it in

disinfectant solution.

  However, it is understood that the production of endoscopes with one-piece rods does not depart from the scope of the present invention. For example, a monobloc endoscope can be produced by permanently securing the optical head 5 and the handle 3 of the endoscope 1 of FIG. 1. However, it may be advantageous to have in a monobloc endoscope (FIG. 3) or even in a removable endoscope (FIG. 2), the sensor 7 in the distal position, near a shooting opening, which makes it possible to simplify the optics of image formation. The example illustrated in FIG. 2 comprises a lighting system similar to that of FIG. 1 with two lamps 11 cooled by a turbine, the flow of cooling air being symbolized by the arrows 35. This solution allows setting up work of color video sensors of average sensitivity of low cost price, while preserving an excellent color fidelity facilitating the interpretation of an image 37 formed on a monitor 39. It should be noted that as in the case of the endoscope 1 of Figures 1 and 2, the air outlets 21

  are located outside the patient's mouth.

  In Figure 3, we can see an alternative embodiment using a light source 11 releasing little heat, which allows its introduction near the objects to be viewed, in particular

  at the distal end of the endoscope 1 near the sensor 7.

  The low heat generation at the distal end of the cane compatible with its introduction into the patient's mouth results from the choice of suitable light source, possibly supplemented by thermal drains directed towards the proximal end of the endoscope 1. One can for example use incandescent lamps of very low power and very good performance. However, in the preferred example illustrated, light-emitting diodes (LED in English terminology) are used. Although the use of black and white video sensors 7 is not beyond the scope of the present invention, it is preferable

  to use a color sensor, which facilitates the interpretation of image 37.

  The lighting of a color image can be obtained by using light sources 11 comprising one or more sets of light-emitting diodes, each set comprising a red diode, a green diode and a blue diode corresponding to the filters of the color photosites of the video sensor. 7. The number of sets of light-emitting diodes depends on the light intensities emitted by each of the light-emitting diodes as well as on the sensitivity of the video sensor 7. Thus, it is particularly advantageous to use

  very high sensitivity video sensors.

  As a variant, a monochrome video sensor 7 is advantageously used, associated with sequential lighting by the red, blue and green light-emitting diodes ensuring the formation of the three

  primary color images allowing the formation of a color image.

  Advantageously, a low monochrome sensor is used

  cost price, high sensitivity and / or high resolution.

  The endoscope according to the present invention typically comprises an external rigid shell made for example of plastic. An alternative embodiment advantageously corresponding to the endoscopes of Figures 2 or 3 equipped with a video sensor 7 located near the distal end of the rod comprises a flexible shell relative to the longitudinal axis of the rod so as to facilitate or to make it possible to access the optical head in places which are curved or whose access requires bending an elbow. Used in medical endoscopy, such endoscopes make it easier and less painful to examine the patient's various organs. Used in industrial endoscopy, such flexible rod endoscopes make it possible to visualize places inaccessible to

rigid endoscopes.

  The flexible endoscope comprises for example flexible plastic sheaths, for example polyurethane, advantageously reinforced by a flexible frame relative to the longitudinal axis increasing the resistance to crushing of the external sheath. In the preferred embodiment of a flexible endoscope according to the present invention, the sheath, in particular made of polyurethane, is armed with a spiral spring whose axis, at rest, is preferably coincident with the longitudinal axis of the cane. The light sources 11 as well as the video sensor 7 are advantageously placed in a capsule, for example metallic, bonded to the distal end of the sheath. In an exemplary embodiment, the rigid capsule is 10 mm in length, the flexible rod advantageously having a length greater than that of the endoscopes

illustrated teeth.

  In Figure 4, we can see an alternative embodiment using a light source 11 emitting little heat advantageously using red, blue and green light emitting diodes (similar to those used in the endoscope of Figure 3), associated with a video sensor 7 arranged in the handle 3 (analogous to the sensor in FIG. 1). Advantageously, the endoscope of FIG. 4 is separable between a handle 3 containing the electronics 9 and the video sensor 7 and an optical head comprising the lighting means and part of the train of lens for forming images.

on the video sensor 7.

  It is understood that the use of endoscope 1 in FIGS. 3 or 4 separable between a handle containing the electronics 9 and an optical head comprising the video sensor 7 does not go beyond the ambit of

the present invention.

  In FIG. 5, we can see a first example of the signal processing device supplied by the sensor 7, example in which the signal processing circuit 9 ensures its amplification and / or a change of frequency allowing its direct display on a monitor analog. In addition, a low frequency video signal can be transmitted

  on a pair of electric wires, which simplifies the construction of the cable 13.

  The example of the image processing circuit of FIG. 6 comprises a modulator 43 providing on an output 45 a composite video signal modulated for example with the SECAM, NTSC or advantageously PAL standard and / or, on an output 47, a video signal with components of

  separate luminescence and chrominance (Y / C in English terminology

  Saxon). The modulator 43 may also include an output (not

  shown) of a low frequency video signal.

  The composite signal, the unmodulated video signal, the low frequency video signal can be connected to a video monitor, or to the low frequency stages of a video recorder or television set (for example by the so-called "PERITELEVISION" socket), the output 45 can be connected to the antenna input of a video recorder or a television whereas output 47 can be connected to the Y / C input of a television or video recorder, in particular a S VHS standard VCR or

a Hi8 standard VCR.

  In FIG. 7, the electronic circuit 9 comprises an analog-digital converter 49 delivering a digital video signal particularly well suited for display on liquid crystal screens (LCD in English terminology) with digital interface. These can be liquid crystal displays without an analog interface and analog digital converters, or screens with a digital input located in addition to an analog interface

downstream of the analog interface.

  In FIG. 8, we can see a signal processing circuit 9 comprising an analog-digital converter 49 whose output is connected to the input of a video card 51 comprising a frame memory 53 advantageously associated with a graphics processor 55 , the output of the frame memory 53 being connected to a digital analog converter 57 delivering on an output 59 a signal of type S VGA (or super video graphic adapter in English terminology) capable of being displayed by a computer monitor. Advantageously, control means make it possible to select the display resolution in order to adapt the resolution of images delivered by the video sensor 7 to the optimal resolution for displaying the screen. The device of FIG. 8 advantageously comprises, in addition, a digital output 60 allowing the optimized display on a liquid crystal screen comprising

a digital interface.

  In FIG. 9, one can see an example of a signal processing device 9 allowing the wireless transmission of video images to a reception device placed nearby, the transmission advantageously taking place over a distance of between 1 and 10 m or more. The device 9 comprises a high frequency modulator 61 whose input is connected directly or via an adaptation circuit (not shown) to the video output of the sensor 7 and whose output is connected via an amplifier 63 to a transmitting antenna 65. A receiving device 67 comprises a receiving antenna 69 connected to a demodulator 71 whose output 73 is connected to display, recording, processing and / or

adapting images.

  It is understood that the present invention is not limited to the use of high frequency wireless links using radio waves, but also extends to the use of other types of waves such as

for example infrared waves.

  Signs from endoscopes according to the present invention can be processed by computers. For example, composite signals from output 45 or Y / C signals from output 47 can be processed by a television reception card (TV tuner in English terminology) or a video capture card d a personal computer, while the digital video signals delivered by the analog-to-digital converter 49

  are likely to be processed by a digital acquisition card.

  The present invention applies in particular to the

  visualization of objects that are difficult to access.

  The present invention applies mainly to

  medical imaging, in particular dental endoscopy.

! I

Claims (13)

  1. Endoscope comprising a light source (11) and a rod, at least the distal end of which is capable of entering a cavity comprising objects to be viewed (33), said rod comprising a video sensor (7), characterized in that that the source of   light (11) is incorporated in the rod carrying the video sensor (7).   2. Endoscope according to claim 1, characterized in that the rod comprises an electronic circuit (9) for shaping the signal delivered by the video sensor (7) so as to make it usable   by a display (39), recording or processing device.   3. Endoscope according to claim 1 or 2, characterized in that the light source (11) comprises at least one incandescent lamp located between the distal and proximal ends of the cane and in that the cane comprises optical fibers (17 ) of light supply between the lamp (11) and the distal end of the rod having a length of between 4 cm and 20 cm, preferably between 6 cm and 14 cm   or more preferably between 8 cm and 12 cm.   4. Endoscope according to claim 3, characterized in that the lamp (11) is a miniature incandescent lamp comprising   a front focusing lens.   5. Endoscope according to any one of the claims   above, characterized in that it comprises means (19, 21) for cooling the light source (11) by forced circulation of air (35).   6. Endoscope according to any one of the claims   above, characterized in that it comprises a video sensor (7), in particular of the charge coupled circuit type, located near   the proximal end of the cane.   7. Endoscope according to any one of the claims   previous, characterized in that the rod is separable to form a handle (3) and an optical head (5) resistant to high temperatures reigning in an autoclave.   8. Endoscope according to any one of claims 1   to 5, characterized in that it comprises a video sensor (7), preferably of the charge coupled circuit type, located near the distal end cane.   9. Endoscope according to any one of claims 1,   2, 6, 7 or 8, characterized in that it includes a light source (11)   arranged near the distal end of the cane.   10. Endoscope according to claim 9, characterized in that the light source (11) has a low heat dissipation. 11. Endoscope according to claim 9 or 10, characterized in that the light source comprises light-emitting diodes   primary colors, including red, green and blue LEDs.   12. Endoscope according to any one of claims   above, characterized in that said endoscope is a dental endoscope.   13. Endoscope according to any one of claims   previous, characterized in that said endoscope includes a cane   flexible with respect to its longitudinal axis.