CN201926621U - Multi-channel photoelectric detection device - Google Patents

Abstract

The utility model relates to a multi-channel photoelectric detection device, which relates to a photoelectric detection device that uses infrared light, visible light or ultraviolet light to test or analyze materials, including a light source signal part, an optical signal transmission part, a photoelectric signal conversion part and a signal acquisition and processing part The device is based on the optical fiber as the light transmission medium, so that the light emitted by the light source is transmitted to the corresponding target through the optical fiber, and the stepping motor is used to drive the rotating rod to rotate to realize the switching of different optical fiber channels and realize the accurate positioning of different measured targets. A multi-channel photoelectric detection device, which overcomes the disadvantages that most of the existing multi-channel photoelectric detection devices use multiple photoelectric detection elements, do not have a stable and consistent optical system, and have poor ability to resist electromagnetic interference and noise interference .

Description

A multi-channel photoelectric detection device

technical field

The technical solution of the utility model relates to a photoelectric detection device that uses infrared light, visible light or ultraviolet light to test or analyze materials, specifically a multi-channel photoelectric detection device.

Background technique

Most of the existing multi-channel photoelectric detection devices use multiple photoelectric detection elements, do not have a stable and consistent optical system, and have poor ability to resist electromagnetic interference and noise interference; in addition, some existing multi-channel photoelectric detection devices The selection of channels is achieved through circuit design, which increases the difficulty of circuit design; there are also some existing multi-channel photoelectric detection devices that are based on optical rearrangement, collimation, and focusing systems. Multiple transmission devices, The light utilization efficiency of the optical multiplex transmission of light beams of such devices is very low, the light is difficult to be collimated really, and the space occupation is large.

Contents of the invention

The technical problem to be solved by the utility model is to provide a multi-channel photoelectric detection device, which is based on the optical fiber as the transmission medium of light, so that the light emitted by the light source is transmitted to the corresponding target through the optical fiber, and the stepping motor is used to drive the rotation Rod rotation realizes the switching of different optical fiber channels and realizes accurate positioning of different measured targets. It overcomes the fact that most of the existing multi-channel photoelectric detection devices use multiple photoelectric detection elements, which do not have stability and consistency. Unique optical system, and poor ability to resist electromagnetic interference and noise interference.

The technical solution adopted by the utility model to solve the technical problem is: a multi-channel photoelectric detection device, including a light source signal part, an optical signal transmission part, a photoelectric signal conversion part and a signal acquisition and processing part; wherein, the light source signal part is an LED light source , the optical signal transmission part is composed of optical fiber bundles, optical fiber inserts, rotating rods and stepping motors, the photoelectric signal conversion part is composed of photocells and conditioning circuits, the signal acquisition and processing part includes acquisition cards, computer interface adapters and computers; LED light source It is installed in the hole at the end of the rotating rod and aligned with a hole of the optical fiber insertion plate. The optical fiber insertion plate and the rotating rod are respectively fixed on the central axis of the stepping motor through screws, and the input end of the optical fiber bundle is fixed on the optical fiber with a clamp. Insert the hole in front of the disc and align it with the hole, the middle end of the optical fiber bundle is led to the measured object, fixed in front of the measured object with a fixture, the photocell is fixed at the output end of the optical fiber bundle, and the electricity converted by the photocell The signal is sent to the input end of the conditioning circuit, the output end of the conditioning circuit is connected to the input connection end of the acquisition card, the digital output connection end of the acquisition card is connected to the computer, the I/O port of the interface adapter of the computer is connected to the pulse input of the stepping motor The interface adapter of the computer's interface adapter is connected to the serial port of the computer at the same time.

The above-mentioned multi-channel photoelectric detection device, wherein the arrangement sequence of the components and the transmission line of the photoelectric signal is selected from any of the following two methods:

The first installation sequence and the transmission line of the photoelectric signal is to fix the input end of the optical fiber bundle in front of the hole of the optical fiber insert plate with a fixture and align it with the hole, as the input end of the light emitted by the LED light source, the LED light source is aligned A hole in the optical fiber insert, the light emitted by the LED light source is transmitted through the optical fiber bundle, focused on the measured object, and the light passing through the measured object is transmitted to the photocell placed at the output end of the optical fiber bundle through the optical fiber bundle, and Received by the photocell, after the photoelectric signal is converted into an electrical signal by the photocell, the electrical signal is sent to the conditioning circuit, and the conditioning circuit modulates, demodulates and amplifies the input electrical signal, and then transmits it to the acquisition card and is collected and converted into a corresponding signal. The acquisition card then sends the digital quantity to the computer for processing, the computer controls the interface adapter of the computer, and controls the stepping motor through the interface adapter of the computer, and the stepping motor drives the rotating rod to rotate, thereby realizing the switch.

The second installation sequence and the transmission line of the photoelectric signal is to fix the lens in front of the LED light source, and then align the input end of the optical fiber bundle with the light homogenized by the lens. As the input end of the light source, the LED light source emits The light passes through the lens, and then the homogenized light is transmitted through the optical fiber bundle and focused on the object to be measured. The other end of the optical fiber bundle is fixed in front of the hole of the optical fiber insert with a clamp and aligned with the hole, and passes through the measured object. The light of the target is transmitted to the photocell placed in a hole aligned with the optical fiber insert through the optical fiber bundle, and is received by the photocell. After the photocell converts the optical signal into an electrical signal, the electrical signal is sent to the conditioning circuit for conditioning The circuit modulates, demodulates and amplifies the input electrical signal, and then transmits it to the acquisition card and is acquired into a corresponding digital quantity. The acquisition card then sends the digital quantity to the computer for processing, and the computer controls the interface adapter of the computer. , and the stepping motor is controlled through the interface adapter of the computer, and the stepping motor drives the rotating rod to rotate, thereby realizing the switching of each light channel.

In the above-mentioned multi-channel photoelectric detection device, the optical fiber insertion plate is a square aluminum plate with a side length of 100 mm and a thickness of 6 mm. The center of the aluminum plate is the center of a circle with a diameter of 90 mm. 3mm circular hole, each with a diameter of 2.5mm screw holes on the four corners of the aluminum plate center 22mm, the distance between each screw hole is 31mm, each of the four corners on the edge of the aluminum plate is provided with A screw hole with a diameter of 2.5 mm, the distance between each screw hole is 88 mm, and a through hole with a diameter of 22 mm is opened in the center of the aluminum plate.

The above-mentioned multi-channel photoelectric detection device, the length of the rotating rod is 100mm, the width is 15mm and the thickness is 8mm, there is a hole with a diameter of 5mm in the center of the front of the rotating rod, and a hole with a diameter of 3mm at its end There is a threaded hole with a diameter of 2mm on the side of the rotating rod.

The above-mentioned multi-channel photoelectric detection device, the conditioning circuit is composed of an inverting input type I/V conversion circuit, a voltage follower circuit, a phase-sensitive detection circuit and a non-inverting amplifier circuit, wherein the inverting input type I/V conversion circuit is as follows: As shown in Figure 8, the voltage follower circuit is shown in Figure 9, the phase-sensitive detection circuit is shown in Figure 10, and the non-inverting amplifier circuit is shown in Figure 11.

The above-mentioned multi-channel photoelectric detection device, the acquisition card is a multifunctional data acquisition card USB2813A, the computer is a common PC, and the interface adapter of the computer is known and can be purchased commercially.

The beneficial effects of the utility model are: the substantive characteristics and significant progress of a multi-channel photoelectric detection device of the utility model are as follows:

(1) The optical fiber is used as the transmission medium of light, which has good electromagnetic insulation performance, small signal attenuation, wide frequency band, long transmission distance and strong anti-interference ability;

(2) The utility model provides a mechanical structure in which a multi-channel optical fiber insert disc is matched with a rotating rod. It realizes the switching of different optical fiber channels and the accurate positioning of different measured objects, and realizes the adaptation of the optical fiber and the LED light source. For this reason, the utility model device only uses one The photoelectric detection device realizes the detection of multi-channel optical signals, thereby reducing the inconsistency among the multiple light sources of the existing multi-channel photoelectric detection device.

In addition, considering that the light transmitted by the optical fiber may be inhomogeneous, which will affect the result of photoelectric detection, the utility model provides two methods for the arrangement sequence of components and the transmission line of photoelectric signals. The difference between the two is that the positions of the photocell and the light source are exchanged. One of the ways is to first focus the scattered light through the lens. Since the light emitted by the LED is not necessarily an ideal uniform light, first use the lens (12) a to focus the parallel light emitted by the LED on the focal point of the lens. Reasonably arrange the positions of lens (12)a and lens (12)b, so that the light focused on the focal point of lens (12)a can exit in parallel after passing through lens (12)b, and send the light into the light guide after obtaining ideal uniform light The fiber bundle is then focused and irradiated onto the measured object, thus ensuring the uniformity of the light transmitted by the optical fiber;

(3) The utility model device uses a cold light source as a light-emitting device, which has very excellent optical and flickering characteristics, and avoids a series of problems caused by heat accumulation, and has the characteristics of high efficiency, energy saving and environmental protection;

(4) The utility model device also provides a conditioning circuit, which includes an I/V conversion circuit, a voltage follower circuit, a phase-sensitive detection circuit and an in-phase amplifying circuit, so as to realize measurement and control of electrical signals;

(5) The utility model device completes the integrated management and control through the computer, adopts the computer as the control core of the system, and uses the data acquisition card on the basis of the computer to improve the acquisition control function. When selecting a data acquisition card to acquire signals, many factors must be considered, such as: input and output configuration, signal input range, sampling frequency, resolution and conversion accuracy, etc. Based on the above considerations, the device of the present invention adopts the multifunctional data acquisition card USB2813A to realize the acquisition and control of signals. The USB2813A acquisition card is a data acquisition card based on the USB bus, which can be directly connected to the USB interface of the computer to form a data acquisition, waveform analysis and system processing system in various fields such as laboratories and product quality inspection centers. Through the interactive information between the USB2813A acquisition card, the computer interface adapter and the computer, the collection, storage, analysis, processing and output of the input optical signal are realized.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

Fig. 1 is a composition block diagram of a multi-channel photoelectric detection device of the present invention.

Fig. 2 is a schematic diagram of the overall structure of a multi-channel photoelectric detection device of the present invention.

Fig. 3 is a schematic diagram of the first installation sequence of the device of the present invention and the transmission mode of the photoelectric signal.

Fig. 4 is a schematic diagram of the second arrangement sequence of the device of the present invention and the transmission mode of the photoelectric signal.

Fig. 5-1 is a front view of the optical fiber insertion disc in the device of the present invention.

Fig. 5-2 is a top view of the optical fiber insertion tray in the device of the present invention.

Fig. 6 is a schematic diagram of the structure of the rotating rod in the device of the present invention.

Fig. 7 is a schematic diagram of the connection of the optical fiber insertion plate, the rotating rod and the stepping motor in the device of the present invention.

Fig. 8 is an inverting input type I/V conversion circuit in the conditioning circuit of the device of the present invention.

Fig. 9 is a voltage follower circuit diagram in the conditioning circuit of the device of the present invention.

Fig. 10 is a circuit diagram of the phase-sensitive detection in the conditioning circuit of the device of the present invention.

Fig. 11 is a non-inverting amplifying circuit diagram in the conditioning circuit of the device of the present invention.

Fig. 12 is a computer work flow diagram 1 in the device of the utility model.

Fig. 13 is a computer working flowchart 2 in the device of the present invention.

In the figure, 1. LED light source, 2. Optical fiber bundle, 3. Optical fiber insertion plate, 4. Rotary rod, 5. Control stepping motor, 6. Computer interface adapter, 7. Photocell, 8. Conditioning circuit, 9. Including acquisition card, 10. computer, 11. target object, 12. lens, 13. screw.

Detailed ways

The embodiment shown in Fig. 1 shows that a multi-channel photoelectric detection device of the present invention includes a light source signal part, an optical signal transmission part, a photoelectric signal conversion part and a signal acquisition and processing part.

The embodiment shown in Fig. 2 shows that the connection of each component in a kind of multi-channel photoelectric detection device of the present utility model is: the LED light source (1) is installed in the hole at the end of the rotating rod (4), and is aligned with the optical fiber insert ( 3), the optical fiber insert (3) and the rotating rod (4) are respectively fixed on the central axis of the stepper motor (5), and the input end of the optical fiber bundle (2) is fixed on the optical fiber insert ( 3) in front of the hole and aligned with the hole, the middle end of the optical fiber bundle (2) is led to the measured object (11), fixed in front of the measured object (11) with a clamp, and the photocell (7) is fixed on the light guide The output end of the fiber bundle (2), the photocell (7) is connected to the conditioning circuit (8), the conditioning circuit (8) is connected to the acquisition card (9), and the acquisition card (9) is connected to the computer (10), and the computer (10) passes the computer The interface adapter (6) is connected with the stepper motor (5), thereby forming the whole multi-channel photoelectric detection device.

The embodiment shown in Fig. 3 shows that the placement sequence of the components and the transmission line of the photoelectric signal in a multi-channel photoelectric detection device of the present utility model are that the input end of the optical fiber bundle (2) is fixed on the optical fiber insert ( 3) in front of the hole and aligned with the hole, as the input end of the light emitted by the LED light source (1), the LED light source (1) is aligned with a hole in the optical fiber insert (3), and the light emitted by the LED light source (1) passes through The optical fiber bundle (2) transmits and focuses on the measured object (11), and the light passing through the measured object (11) is transmitted to the photocell placed at the output end of the optical fiber bundle (2) through the optical fiber bundle (2) (7), and received by the photocell (7), after the light signal is converted into an electrical signal by the photocell (7), the electrical signal is sent to the conditioning circuit (8), and the conditioning circuit (8) modulates the input electrical signal , after demodulation and amplification, pass to acquisition card (9) and be collected and become corresponding digital quantity, and acquisition card (9) sends this digital quantity to computer (10) to process again, and computer (10) is to computer's The interface adapter (6) controls, and controls the stepping motor (5) through the interface adapter (6) of the computer, and the stepping motor (5) drives the rotating rod (4) to rotate, thereby realizing the switching of each light channel.

The embodiment shown in Fig. 4 shows that the placement sequence of the components and the transmission line of the photoelectric signal in a multi-channel photoelectric detection device of the present utility model are that the lens (12) is fixed in front of the LED light source (1), and then the optical fiber The input end of the beam (2) is aligned with the light homogenized by the lens (12). As the input end of the light source, the light emitted by the LED light source (1) passes through the lens (12). Since the light emitted by the LED is not necessarily ideal Therefore, first use lens (12) a to focus the parallel light emitted by the LED on the focal point of this lens, and in addition, by rationally arranging the positions of lens (12) a and lens (12) b, make the focus on the lens ( 12) After passing through the lens (12) b, the light at the focal point of a can exit in parallel to obtain an ideal uniform light, and then transmit the homogenized light through the optical fiber bundle (2) to focus on the measured object (11) , the other end of the optical fiber bundle (2) is fixed in front of the hole of the optical fiber insert (3) with a clamp and aligned with the hole, the light passing through the measured object (11) is transmitted to the place through the optical fiber bundle (2) A photocell (7) aligned with a hole in the optical fiber insert (3) is received by the photocell (7), and after the photocell (7) converts the light signal into an electrical signal, the electrical signal is sent to the conditioning circuit (8 ), the conditioning circuit (8) modulates, demodulates and amplifies the input electrical signal and then transmits it to the acquisition card (9) and is acquired to become a corresponding digital quantity, and the acquisition card (9) sends the digital quantity to the The computer (10) processes, and the computer (10) controls the interface adapter (6) of the computer, and controls the stepping motor (5) through the interface adapter (6) of the computer, and the stepping motor (5) drives the rotating rod (4 ) is rotated to realize the switching of each light channel.

The embodiment shown in Figure 5-1 shows that the side length of the optical fiber insert disc (3) in a multi-channel photoelectric detection device of the present invention is a 100mm square aluminum plate, and 50 evenly distributed on the circle whose center is the center of the aluminum plate Circular holes with the same diameter of 3mm are provided with a screw hole with a diameter of 2.5mm on each of the four corners 22mm away from the center of the aluminum plate, and the distance between each screw hole is 31mm. Each corner is provided with a screw hole with a diameter of 2.5 mm, the distance between each screw hole is 88 mm, and a through hole with a diameter of 22 mm is opened in the center of the aluminum plate.

The embodiment shown in Fig. 5-1 shows that the thickness of the optical fiber insert disc (3) in a kind of multi-channel photoelectric detection device of the present invention is 6mm, and the diameter of the circle evenly distributed by the circular tunnel is 90mm.

The embodiment shown in Figure 6a and Figure 6b shows that the length of the rotating rod (4) in a kind of multi-channel photoelectric detection device of the present utility model is 100mm, the width is 15mm and the thickness is 8mm, and there is A 5mm diameter hole with a 3mm diameter hole at its end and a 2mm diameter threaded hole designed into the side of the swivel rod.

The embodiment shown in Figure 7 shows that the rotating rod (4) in a kind of multi-channel photoelectric detection device of the present utility model is fixed on the central axis of the stepping motor (5) with a screw (13), and the optical fiber inserting disc ( 3) Fix it on the middle shaft of the stepper motor (5) with two screws (13).

The embodiment shown in Figure 8 shows that the inverting input type I/V conversion circuit of the conditioning circuit (8) in a kind of multi-channel photoelectric detection device of the present utility model, I/V conversion is used for converting the input current signal into The output voltage signal in a linear relationship, when measuring a small current, converts the small current into a voltage, and usually passes the converted current through a resistor R. According to Ohm's law, the voltage drop on the resistor R is the conversion result.

The embodiment shown in Figure 9 shows that the voltage following circuit diagram of the conditioning circuit (8) in a multi-channel photoelectric detection device of the present utility model, after the I/V conversion of each signal, the output impedance is relatively high, if the input of the rear stage If the impedance is relatively small, a considerable part of the signal will be lost in the output resistance of the previous stage. In order to avoid this phenomenon, a voltage follower needs to be used, so that it can be buffered.

The embodiment shown in Figure 10 shows that the precise phase-sensitive detection circuit of the conditioning circuit (8) in a multi-channel photoelectric detection device of the present invention, in order to extract the measurement signal reflecting the measured value from the modulated signal, it is necessary to The measured signal is demodulated.

The embodiment shown in Fig. 11 shows that the utility model is an in-phase amplifying circuit of the conditioning circuit (8) in a multi-channel photoelectric detection device. Since the measured object itself is a weak quantity and is limited by the sensitivity of various sensors, the obtained power is naturally a small signal and generally cannot be directly used for sampling processing. The non-inverting amplification circuit is to amplify the weak signal enough to perform various conversion processing, or to push the indicator and recorder control mechanism.

The embodiment shown in Figure 12 shows that one of the computer workflows in a kind of multi-channel photoelectric detection device of the present utility model is:

Start→System initialization→Signal collection→Data processing to get the result→Storing the collection result and information→Print the result.

Thus, the storage, analysis, calculation and result output of the data collected by the computer (10) to the acquisition card (9) are realized.

The embodiment shown in Figure 13 shows that the second of the computer workflow in a kind of multi-channel photoelectric detection device of the utility model is:

Start → System Initialization → Is there a key pressed? No→return to system initialization; yes→execute the corresponding button function→end.

Thus, the computer (10) controls the interface adapter (6) of the computer, and controls the stepping motor (5) through the interface adapter (6) of the computer.

Example 1

The LED light source (1) is installed in the hole at the end of the rotating rod (4) and aligned with a hole of the fiber insert (3), and the fiber insert (3) and the rotating rod (4) are respectively fixed by screws (13) On the central axis of the stepper motor (5), the input end of the optical fiber bundle (2) is fixed in front of the hole of the optical fiber insert (3) with a clamp and aligned with the hole, and the middle end of the optical fiber bundle (2) is guided To the measured object (11), fix it in front of the measured object (11) with a clamp, fix the photocell (7) on the output end of the optical fiber bundle (2), and send the electrical signal converted by the photocell (7) into the The input end of the conditioning circuit (8), the output end of the conditioning circuit (8) is connected to the input connection end of the acquisition card (9), the digital output connection end of the acquisition card (9) is connected to the computer (10), and the interface adapter of the computer The I/O port of (6) is connected with the pulse input terminal of the stepper motor (5), and the interface adapter of the computer's interface adapter (6) is connected to the serial port of the computer (10) simultaneously. The placement sequence of the above-mentioned components and the transmission line of the photoelectric signal are to fix the input end of the optical fiber bundle (2) in front of the hole of the optical fiber insert (3) with a clamp and align it with the hole, as the LED light source (1) emits The input end of the light, the LED light source (1) is aimed at a hole of the optical fiber insert (3), the light emitted by the LED light source (1) is transmitted through the optical fiber bundle (2), and focused on the measured object (11), The light passing through the measured object (11) is transmitted to the photocell (7) placed at the output end of the fiber optic bundle (2) through the optical fiber bundle (2), and is received by the photocell (7). After the optical signal is converted into an electrical signal, the electrical signal is sent to the conditioning circuit (8), and the conditioning circuit (8) modulates, demodulates and amplifies the input electrical signal, and then transmits it to the acquisition card (9) and is collected and transformed. For the corresponding digital quantity, the acquisition card (9) sends the digital quantity to the computer (10) for processing, and the computer (10) controls the interface adapter (6) of the computer, and controls the interface adapter (6) by the computer. The stepping motor (5), the stepping motor (5) drives the rotation rod (4) to rotate, and then realizes the adaptation of the photocell (7) to different holes on the optical fiber insert (3) and the switching of each light channel. This constitutes a whole of a multi-channel photoelectric detection device of the present invention. Among them, the LED light source (1) constitutes the light source signal part, the optical fiber bundle (2), the optical fiber insertion plate (3), the rotating rod (4) and the stepping motor (5) constitute the optical signal transmission part, the photocell (7) and the conditioning The circuit (8) constitutes the photoelectric signal conversion part, and the acquisition card (9), the computer interface adapter (6) and the computer (10) constitute the main body of the signal acquisition and processing part.

The optical fiber insertion plate used in this embodiment is a square aluminum plate with a side length of 100 mm and a thickness of 6 mm. The center of the aluminum plate is the center of a circle, and 50 circular channels with the same size and a diameter of 3 mm are evenly distributed on a circle with a diameter of 90 mm. , There is a screw hole with a diameter of 2.5mm on each of the four corners 22mm away from the center of the aluminum plate. Holes, the mutual spacing of each screw hole is 88mm, and a through hole with a diameter of 22mm is opened in the center of the aluminum plate.

The length of the rotating rod used in this embodiment is 100mm, the width is 15mm and the thickness is 8mm. There is a hole with a diameter of 5mm at the center of the front of the rotating rod and a hole with a diameter of 3mm at its end. The side design has a threaded hole with a diameter of 2mm.

The conditioning circuit used in this embodiment is composed of an inverting input type I/V conversion circuit, a voltage follower circuit, a phase-sensitive detection circuit, and a non-inverting amplifier circuit. Among them, the inverting input type I/V conversion circuit is shown in Figure 8. The follower circuit is shown in Figure 9, the phase-sensitive detection circuit is shown in Figure 10, and the non-inverting amplifier circuit is shown in Figure 11.

The acquisition card used in this embodiment is a multi-function data acquisition card USB2813A, the computer is an ordinary PC, and the interface adapter of the computer is well known and can be purchased commercially.

Example 2

The LED light source (1) is installed in the hole at the end of the rotating rod (4) and aligned with a hole of the fiber insert (3), and the fiber insert (3) and the rotating rod (4) are respectively fixed by screws (13) On the central axis of the stepper motor (5), the input end of the optical fiber bundle (2) is fixed in front of the hole of the optical fiber insert (3) with a clamp and aligned with the hole, and the middle end of the optical fiber bundle (2) is guided To the measured object (11), fix it in front of the measured object (11) with a clamp, fix the photocell (7) on the output end of the optical fiber bundle (2), and send the electrical signal converted by the photocell (7) into the The input end of the conditioning circuit (8), the output end of the conditioning circuit (8) is connected to the input connection end of the acquisition card (9), the digital output connection end of the acquisition card (9) is connected to the computer (10), and the interface adapter of the computer The I/O port of (6) is connected with the pulse input terminal of the stepper motor (5), and the interface adapter of the computer's interface adapter (6) is connected to the serial port of the computer (10) simultaneously. The placement sequence of the above components and the transmission line of the photoelectric signal are to fix the lens (12) before the LED light source (1), and then the input end of the optical fiber bundle (2) and the light homogenized by the lens (12) Alignment, as the input end of the light source, the light emitted by the LED light source (1) passes through the lens (12). Since the light emitted by the LED is not necessarily an ideal uniform light, first use the lens (12) a to parallel the light emitted by the LED. The light is focused on the focal point of the lens, and by rationally arranging the positions of the lens (12) a and the lens (12) b, the light focused on the focal point of the lens (12) a can exit in parallel after passing through the lens (12) b, Get the ideal uniform light, and then transmit the homogenized light through the optical fiber bundle (2), focus on the measured object (11), and fix the other end of the optical fiber bundle (2) to the optical fiber insert ( 3) in front of the hole and aligned with the hole, the light passing through the measured object (11) is transmitted through the optical fiber bundle (2) to the photocell (7) placed in a hole aligned with the optical fiber insert (3), And received by the photocell (7), after the light signal is converted into an electrical signal by the photocell (7), the electrical signal is sent to the conditioning circuit (8), and the conditioning circuit (8) modulates, demodulates and After amplifying, transmit to acquisition card (9) and be collected and become corresponding digital quantity, and acquisition card (9) sends this digital quantity to computer (10) to process again, and computer (10) is to the interface adapter (6) of computer ) is controlled, and the stepping motor (5) is controlled by the interface adapter (6) of the computer, and the stepping motor (5) drives the rotating rod (4) to rotate, thereby realizing the switching of each light channel. This constitutes a whole of a multi-channel photoelectric detection device of the present invention. Among them, the LED light source (1) constitutes the light source signal part, the optical fiber bundle (2), the optical fiber insertion plate (3), the rotating rod (4) and the stepping motor (5) constitute the optical signal transmission part, the photocell (7) and the conditioning The circuit (8) constitutes the photoelectric signal conversion part, and the acquisition card (9), the computer interface adapter (6) and the computer (10) constitute the main body of the signal acquisition and processing part.

The optical fiber insertion plate used in this embodiment is a square aluminum plate with a side length of 100 mm and a thickness of 6 mm. The center of the aluminum plate is the center of a circle, and 50 circular channels with the same size and a diameter of 3 mm are evenly distributed on a circle with a diameter of 90 mm. , There is a screw hole with a diameter of 2.5mm on each of the four corners 22mm away from the center of the aluminum plate. Holes, the mutual spacing of each screw hole is 88mm, and a through hole with a diameter of 22mm is opened in the center of the aluminum plate.

The length of the rotating rod used in this embodiment is 100mm, the width is 15mm and the thickness is 8mm. There is a hole with a diameter of 5mm at the center of the front of the rotating rod and a hole with a diameter of 3mm at its end. The side design has a threaded hole with a diameter of 2mm.

The conditioning circuit used in this embodiment is composed of an inverting input type I/V conversion circuit, a voltage follower circuit, a phase-sensitive detection circuit, and a non-inverting amplifier circuit. Among them, the inverting input type I/V conversion circuit is shown in Figure 8. The follower circuit is shown in Figure 9, the phase-sensitive detection circuit is shown in Figure 10, and the non-inverting amplifier circuit is shown in Figure 11.

The acquisition card used in this embodiment is a multi-function data acquisition card USB2813A, the computer is an ordinary PC, and the interface adapter of the computer is well known and can be purchased commercially.

Example 3

The multi-channel photoelectric detection device prepared in embodiment 1 or embodiment 2 is used to carry out the evaluation experiment of the effectiveness of antibiotics, and the steps are: the liquid medium containing antibiotics of different concentrations is used as the measured object (11), and the multiple-channel photoelectric detection device used is opened. The power supply and light source of the photoelectric detection device measure the growth of the same amount of experimental bacteria liquid in different concentrations of antibiotic liquid culture medium by photometry, and the light passing through the measured object (11) passes through the optical fiber bundle (2) It is transmitted to the photocell (7) and received by the photocell (7). After the photocell (7) converts the light signal into an electrical signal, the electrical signal is sent to the conditioning circuit (8), and the conditioning circuit (8) controls the input electrical signal. After the signal is modulated, demodulated and amplified, it is transmitted to the acquisition card (9) and collected into a corresponding digital quantity, and the acquisition card (9) sends the digital quantity to the computer (10) for processing, and the computer (10) The interface adapter (6) of the computer is controlled, and the stepping motor (5) is controlled through the interface adapter (6) of the computer, and the stepping motor (5) drives the rotating rod (4) to rotate, thereby realizing the switching of each light channel. Finally, the computer (10) stores, analyzes, calculates and processes all the tested signal data and outputs the results to complete the evaluation of the efficacy of the experimental antibiotic.

Claims (4)

1. A multi-channel photoelectric detection device is characterized in that: it comprises a light source signal part, an optical signal transmission part, a photoelectric signal conversion part and a signal acquisition processing part; wherein, the light source signal part is an LED light source, and the light signal transmission part is made of an optical fiber The photoelectric signal conversion part is composed of a photocell and a conditioning circuit, and the signal acquisition and processing part includes an acquisition card, a computer interface adapter and a computer; the LED light source is installed in the hole at the end of the rotating rod , and align it with a hole in the fiber insert, the fiber insert and the rotating rod are respectively fixed on the central axis of the stepper motor through screws, and the input end of the optical fiber bundle is fixed in front of the hole of the fiber insert with a clamp and aligned The middle end of the optical fiber bundle is led to the measured object, fixed in front of the measured object with a fixture, the photocell is fixed at the output end of the optical fiber bundle, and the electrical signal converted by the photocell is sent to the input end of the conditioning circuit , the output end of the conditioning circuit is connected to the input connection end of the acquisition card, the digital output connection end of the acquisition card is connected to the computer, the I/O port of the computer interface adapter is connected to the pulse input end of the stepping motor, and the computer interface adapter interface adapter to the serial port of the computer. 2. A multi-channel photoelectric detection device according to claim 1, characterized in that: wherein the placement sequence of the components and the transmission line of the photoelectric signal are selected from any one of the following two methods: The first installation sequence and the transmission line of the photoelectric signal is to fix the input end of the optical fiber bundle in front of the hole of the optical fiber insert plate with a fixture and align it with the hole, as the input end of the light emitted by the LED light source, the LED light source is aligned A hole in the optical fiber insert, the light emitted by the LED light source is transmitted through the optical fiber bundle, focused on the measured object, and the light passing through the measured object is transmitted to the photocell placed at the output end of the optical fiber bundle through the optical fiber bundle, and Received by the photocell, after the photoelectric signal is converted into an electrical signal by the photocell, the electrical signal is sent to the conditioning circuit, and the conditioning circuit modulates, demodulates and amplifies the input electrical signal, and then transmits it to the acquisition card and is collected and converted into a corresponding signal. The acquisition card then sends the digital quantity to the computer for processing, the computer controls the interface adapter of the computer, and controls the stepping motor through the interface adapter of the computer, and the stepping motor drives the rotating rod to rotate, thereby realizing the switching; The second installation sequence and the transmission line of the photoelectric signal is to fix the lens in front of the LED light source, and then align the input end of the optical fiber bundle with the light homogenized by the lens. As the input end of the light source, the LED light source emits The light passes through the lens, and then the homogenized light is transmitted through the optical fiber bundle and focused on the object to be measured. The other end of the optical fiber bundle is fixed in front of the hole of the optical fiber insert with a clamp and aligned with the hole, and passes through the measured object. The light of the target is transmitted to the photocell placed in a hole aligned with the optical fiber insert through the optical fiber bundle, and is received by the photocell. After the photocell converts the optical signal into an electrical signal, the electrical signal is sent to the conditioning circuit. The conditioning circuit modulates, demodulates and amplifies the input electrical signal, and then transmits it to the acquisition card and is collected and converted into a corresponding digital quantity. Control, and control the stepping motor through the interface adapter of the computer, the stepping motor drives the rotating rod to rotate, and then realizes the switching of each light channel. 3. A multi-channel photoelectric detection device according to claim 1, characterized in that: the optical fiber insert is a square aluminum plate with a side length of 100 mm and a thickness of 6 mm, and the center of the aluminum plate is a circle with a diameter of 90 mm There are 50 circular holes with the same size and a diameter of 3mm evenly distributed on the surface, and a screw hole with a diameter of 2.5mm is provided on each of the four corners 22mm away from the center of the aluminum plate, and the distance between each screw hole is 31mm , A screw hole with a diameter of 2.5 mm is respectively provided on the four corners of the edge of the aluminum plate, and the distance between each screw hole is 88 mm, and a through hole with a diameter of 22 mm is opened in the center of the aluminum plate. 4. A multi-channel photoelectric detection device according to claim 1, characterized in that: the length of the rotating rod is 100mm, the width is 15mm and the thickness is 8mm, and there is a diameter of 5mm at the center of the front of the rotating rod. There is a hole with a diameter of 3mm at its end, and a threaded hole with a diameter of 2mm is designed on the side of the rotating rod. the

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