Multispectral filtering device

Abstract

The invention relates to the technical field of experimental equipment, and discloses a multispectral filtering device which comprises a control circuit, a shell, a first filtering wheel, a first rotary driving mechanism, a second filtering wheel and a second rotary driving mechanism. The first filtering wheel and the second filtering wheel are both rotationally arranged in the shell, the upper surface and the lower surface of the shell are each provided with an observation window, and the positions of the two observation windows coincide. The first filtering wheel and the second filtering wheel are each provided with a plurality of optical filters with different passing wave bands, and the first rotary driving mechanism is used for driving the first filtering wheel to rotate so that the optical filters on the first filtering wheel can be overlapped with the observation windows one by one. The second rotary driving mechanism is used for driving the second filtering wheel to rotate, so that the optical filters on the second filtering wheel can be overlapped with the observation window one by one, and the two rotary driving mechanisms are electrically connected with the control circuit. The multispectral filtering device can flexibly adjust the wave band width of band-pass filtering light or notch filtering light, the experiment convenience is improved, and the experiment cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of experimental equipment, and in particular to a multi-spectral filtering device. Background Art

[0002] In scientific research activities, such as biomedical research, it is necessary to perform optical imaging of tissues or cells in living animals. During the imaging process, it is necessary to observe the image of the object under ambient light or excitation light in a specific wavelength range. In order to facilitate the rapid switching of light bands, a filter wheel is usually set on the optical path. By turning the filter wheel to switch the filter in the optical path, the wavelength of the light is changed. However, the filters on the filter wheel can usually only achieve high-pass or low-pass filtering. To achieve bandpass filtering, it is necessary to specially customize filters coated with double-layer films, which is expensive and cannot flexibly adjust the band range of the bandpass, making it inconvenient to use. Summary of the invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a multi-spectral filtering device that can adjust the band width of the bandpass filter, reduce the number of customized filters required for the experiment, improve the flexibility of adjusting the filter range during the experiment, and reduce the experimental cost.

[0004] To solve the above problems, the technical solution adopted by the present invention is as follows: a multi-spectral filtering device, comprising a control circuit, a housing, a first filter wheel, a first rotation drive mechanism, a second filter wheel and a second rotation drive mechanism, the first filter wheel and the second filter wheel are both rotatably arranged in the housing, the upper and lower surfaces of the housing are each provided with an observation window, the observation window on the upper surface coincides with the observation window on the lower surface, the first filter wheel and the second filter wheel are both provided with a plurality of filters with different pass bands, the distance from the center of the filter on the first filter wheel to the rotation center of the first filter wheel is the same, the distance from the center of the filter on the second filter wheel to the rotation center of the second filter wheel is the same, the first rotation drive mechanism is used to drive the first filter wheel to rotate so that the filters on the first filter wheel can coincide with the observation window one by one, the second rotation drive mechanism is used to drive the second filter wheel to rotate so that the filters on the second filter wheel can coincide with the observation window one by one, and the first rotation drive mechanism and the second rotation drive mechanism are both electrically connected to the control circuit.

[0005] Compared with the prior art, the beneficial effect of the present invention is that the first filter wheel and the second filter wheel can be driven by the first rotation drive mechanism and the second rotation drive mechanism to rotate respectively, so as to switch the wavelength bands of the filters of the first filter wheel and the second filter wheel that coincide with the observation window of the housing. Since the light will pass through the filters on the first filter wheel and the second filter wheel in sequence, if the filters on the first filter wheel and the second filter wheel are high-pass filters and low-pass filters respectively, bandpass filtering or notch filtering of different widths can be achieved by rotating the first filter wheel and the second filter wheel, thereby avoiding the customization of a large number of expensive bandpass filters or notch filters for different experimental needs, reducing the experimental cost, and improving the convenience of adjusting the light band.

[0006] In the above-mentioned multi-spectral filtering device, the rotation centers of the first filter wheel and the second filter wheel coincide with each other.

[0007] In the above-mentioned multi-spectral filtering device, the first filter wheel and the second filter wheel have the same structure, a rotating shaft seat is arranged on the upper surface of the first filter wheel and the second filter wheel, and a rotating shaft matching the rotating shaft seat is arranged on the lower surface of the first filter wheel and the second filter wheel.

[0008] In the above-mentioned multi-spectrum filtering device, the rotation connection between the second filter wheel and the housing, and the rotation connection between the first filter wheel and the second filter wheel are both made of self-lubricating engineering plastics.

[0009] In the above-mentioned multi-spectral filtering device, teeth are arranged on the circumferential surface of the first filter wheel and the second filter wheel, the first rotation drive mechanism and the second rotation drive mechanism both include a motor, an encoder and a transmission gear, the transmission gear and the encoder are both connected to the output shaft of the motor, the transmission gear is meshed with the teeth on the corresponding first filter wheel or the second filter wheel, and the motor and the encoder are electrically connected to the control circuit.

[0010] In the above-mentioned multi-spectral filtering device, baffles are provided on the first filter wheel and the second filter wheel, and two photoelectric switches are provided in the shell for detecting the positions of the baffles on the first filter wheel and the baffles on the second filter wheel respectively, and the two photoelectric switches are electrically connected to the control circuit.

[0011] The above-mentioned multi-spectral filtering device, the control circuit includes a main controller, a power supply circuit, a motor drive circuit, a key circuit and a communication circuit, the output ends of the key circuit and the communication circuit are electrically connected to the main controller, the input end of the motor drive circuit is electrically connected to the main controller, the output end of the motor drive circuit is electrically connected to the motors in the first rotation drive mechanism and the second rotation drive mechanism, and the power supply circuit is used to supply power to the control circuit.

[0012] In the above-mentioned multi-spectral filtering device, the control circuit also includes a current feedback circuit, the input end of the current feedback circuit is electrically connected to the motors in the first rotation drive mechanism and the second rotation drive mechanism, and the output end of the current feedback circuit is electrically connected to the main controller.

[0013] In the above-mentioned multi-spectrum filtering device, the power supply circuit includes a rectifier and filter circuit, a first buck circuit and a second buck circuit connected in sequence.

[0014] In the above-mentioned multi-spectral filtering device, the filters on one of the first filter wheel and the second filter wheel are both high-pass filters, and the filters on the other of the first filter wheel and the second filter wheel are both low-pass filters.

[0015] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a cross-sectional view of a multi-spectral filtering device according to an embodiment of the present invention;

[0017] Figure 2 A top view of a first filter wheel according to an embodiment of the present invention;

[0018] Figure 3 is a cross-sectional view of two filter wheels according to an embodiment of the present invention;

[0019] Figure 4 is a top view of a housing according to an embodiment of the present invention;

[0020] Figure 5 is a schematic diagram of a control circuit according to an embodiment of the present invention;

[0021] Figure 6 is a circuit schematic diagram of a main controller according to an embodiment of the present invention;

[0022] Figure 7 is a schematic diagram of a communication circuit according to an embodiment of the present invention;

[0023] Figure 8 is a schematic diagram of a rectifier and filter circuit according to an embodiment of the present invention;

[0024] Fig. 9 is a schematic diagram of a first step-down circuit according to an embodiment of the present invention;

[0025] Fig.10 is a schematic diagram of a second step-down circuit according to an embodiment of the present invention;

[0026] Fig.11 is a schematic diagram of a motor drive circuit according to an embodiment of the present invention;

[0027] Fig.12 4 is a schematic diagram of a current feedback circuit according to an embodiment of the present invention.

[0028] Description of Figure Numbers:

[0029] 100 housing, 110 observation window, 120 motor avoidance hole, 200 first filter wheel, 210 filter, 220 rotating shaft seat, 230 rotating shaft, 240 baffle, 300 second filter wheel, 400 first rotation drive mechanism, 410 motor, 420 transmission gear, 500 second rotation drive mechanism, 600 photoelectric switch. DETAILED DESCRIPTION

[0030] The embodiments of the present invention are described in detail below. Figure 1 , Figure 2 and Figure 4The embodiment of the present invention provides a multi-spectral filtering device, comprising a housing 100, a first filter wheel 200 and a second filter wheel 300 rotatably disposed in the housing 100, a first rotation drive mechanism 400, a second rotation drive mechanism 500 and a control circuit. The first filter wheel 200 and the second filter wheel 300 are both embedded with a plurality of filters 210 with different passing bands, the distances from the center of the filter 210 on the first filter wheel 200 to the rotation center of the first filter wheel 200 are equal, and the distances from the center of the filter 210 on the second filter wheel 300 to the rotation center of the second filter wheel 300 are equal. Observation windows 110 are both disposed on the upper surface and the lower surface of the housing 100, and the observation window 110 on the upper surface of the housing 100 overlaps with the observation window 110 on the lower surface. The first rotation drive mechanism 400 and the second rotation drive mechanism 500 are both connected to the control circuit, and can respectively drive the first filter wheel 200 and the second filter wheel 300 to rotate under the control of the control circuit. The size of the observation window 110 matches the size of the filters 210 on the first filter wheel 200 and the second filter wheel 300, and the distance from the center of the observation window 110 to the rotation center of the first filter wheel 200 is the same as the distance from the center of the filters 210 on the first filter wheel 200 to the rotation center of the first filter wheel 200, so that when the first filter wheel 200 rotates, the filters 210 on the first filter wheel 200 can overlap with the observation window 110 one by one; the distance from the center of the observation window 110 to the rotation center of the second filter wheel 300 is the same as the distance from the center of the filters 210 on the second filter wheel 300 to the rotation center of the second filter wheel 300, so that when the second filter wheel 300 rotates, the filters 210 on the second filter wheel 300 can overlap with the observation window 110 one by one.

[0031] The multi-spectral filtering device of the embodiment of the present invention is arranged in front of the lens or light source of the imaging device, so that the light passing through the observation window 110 can sequentially pass through the filters 210 on the first filter wheel 200 and the second filter wheel 300. By setting the two filters 210 on the first filter wheel 200 and the second filter wheel 300 that overlap with the observation window 110 as high-pass filters and low-pass filters respectively, the light passing through can be band-pass filtered or notch filtered. At the same time, the two filter wheels are driven to rotate by two rotating drive mechanisms, so that the filters 210 with different passing bands are switched to overlap with the observation window 110, so as to adjust the band width of the band-pass filtering or notch filtering. The multi-spectral filtering device can realize band-pass filtering or notch filtering of multiple different widths by only one set of devices, thereby avoiding the customization of multiple expensive band-pass filters or notch filters for different experimental imaging requirements, improving the convenience of adjusting the filtering range in the experiment, and reducing the experimental cost.

[0032] It is understandable that the rotation centers of the two filter wheels may or may not coincide. Figure 1 and Figure 3 In this embodiment, the first filter wheel 200 and the second filter wheel 300 have the same structure. Taking the first filter wheel 200 as an example, a shaft seat 220 is provided on the upper surface of the first filter wheel 200, and a shaft 230 matching the shaft seat 220 is provided on the lower surface of the first filter wheel 200. Multiple filter wheels can be stacked to achieve mutual rotation connection, so as to save space of the device and avoid the lateral area of ​​the device being too large. In this embodiment, the shaft 230 of the first filter wheel 200 located at the upper part is inserted into the shaft seat 220 of the second filter wheel 300 located at the lower part, and the shaft 230 of the second filter wheel 300 is inserted into the shaft seat in the housing 100. At the same time, in order to further reduce the complexity of the rotation connection between the two filter wheels and the housing 100 and facilitate the replacement of the filter wheels, the rotating shaft 230 and the rotating shaft seat 220 of the first filter wheel 200 and the second filter wheel 300, as well as the rotating shaft seat 220 on the housing 100 are made of self-lubricating engineering plastics such as polyoxymethylene POM, PEEK or igli dur engineering plastics, with low friction, so that smooth rotation can be achieved without the need to set bearings, which facilitates the disassembly, replacement and maintenance of the filter wheels. In this embodiment, the entire first filter wheel 200, the second filter wheel 300 and the housing 100 are completely made of igli dur engineering plastics, which are lighter in weight and can be driven by a small motor 410, further reducing the volume, cost and weight of the device. The base and side walls of the housing 100 are integrally formed, and a detachable top cover is provided at the upper end to facilitate the replacement of the filter wheels. It is understandable that a third filter wheel, a fourth filter wheel, etc. may be provided in the housing 100 to provide more filter band options. An ordinary lens may be provided on each filter wheel, so that it can cooperate with other filters 210 to achieve separate high-pass or low-pass filtering.

[0033] For ease of adjustment, in some embodiments, the filters 210 on one of the two filters 210 are all high-pass filters, and the filters 210 on the other are all low-pass filters. In this embodiment, the wavelength range of the filters 210 on the first filter wheel 200 and the second filter wheel 300 is 560nm to 760nm, and 22 filters 210 are arranged on each filter wheel. The filtering wavelength ranges of adjacent filters 210 differ by 20nm. The filters 210 on the first filter wheel 200 are all low-pass filters, and the filters 210 on the second filter wheel 300 are all high-pass filters. When the excitation peak and emission peak of a dye are around 550nm and 570nm respectively, the first filter 210 can be rotated to make the 580nm low-pass filter coincide with the observation window 110, and the second filter 210 can be rotated to make the 560nm high-pass filter coincide with the observation window 110, so as to form a bandpass filter with a wavelength range of 560nm to 580nm, so as to remove the influence of other ambient light on the imaging effect of the dye.

[0034] Reference Figure 1 and Figure 2 In this embodiment, in order to realize independent driving of the first filter wheel 200 and the second filter wheel 300 whose rotation centers coincide with each other without interfering with each other, the first rotation drive mechanism 400 and the second rotation drive mechanism 500 both include a motor 410 and a transmission gear 420, and the first filter wheel 200 and the second filter wheel 300 are gears with teeth arranged on the circumference. Taking the first rotation drive mechanism 400 as an example, the motor 410 is a hollow cup motor 410 with an encoder, and the output shaft of the motor 410 is connected to the transmission gear 420 shaft, and the transmission gear 420 is meshed with the circumference of the first filter wheel 200. Figure 4, two motor avoidance holes 120 are arranged on the upper cover of the housing 100, so that the tails of the hollow cup motors 410 of the two rotating drive mechanisms can be extended out of the housing 100, and the control cables of the motors 410 can be electrically connected to the control circuit. The lower surfaces of the first filter wheel 200 and the second filter wheel 300 are both provided with baffles 240, which are used as the origins of the first filter wheel 200 and the second filter wheel 300. The baffles 240 should extend a certain distance from the edge of the first filter wheel 200 or the second filter wheel 300 so as to be detected by the two photoelectric switches 600 correspondingly arranged in the housing 100. In this embodiment, the two photoelectric switches 600 are both dustproof slot-type optical couplers, and the heights of the two photoelectric switches 600 match the heights of the corresponding baffles 240, so that the baffles 240 can pass through the detection slots of the corresponding photoelectric switches 600 as the corresponding filter wheels rotate. The motor 410, the encoder and the photoelectric switch 600 are all electrically connected to the control circuit and are controlled by the control circuit. It is understandable that if the rotation centers of the two filter wheels do not coincide, the rotation shafts 230 of the two filter wheels may be directly connected to the output shafts of the two motors 410 respectively, so as to realize independent driving of the rotation of the two filter wheels.

[0035] Reference Figure 5 , the control circuit includes a main controller, a power supply circuit, a motor drive circuit, a key circuit and a communication circuit. The output ends of the key circuit and the communication circuit are both electrically connected to the main controller. The key circuit is used for human-computer interaction to control the rotation of the first filter wheel 200 and the second filter wheel 300. The communication circuit is used for data transmission to set parameters or remote control. The input end of the motor drive circuit is electrically connected to the main controller, and the output end is connected to the motor 410 in the two rotating drive mechanisms to drive the motor 410 to work. The power supply circuit is used to supply power to the entire control circuit, and the encoder and the photoelectric switch 600 are both electrically connected to the main controller. In some embodiments, the control circuit also includes a current feedback circuit, the input end of the current feedback circuit is electrically connected to the motor 410, and the output end is electrically connected to the main controller, which is used to detect the current of the motor 410 to determine whether the motor 410 is blocked or other abnormal conditions.

[0036] Reference Figure 6 In this embodiment, the main controller U8 uses a single-chip microcomputer of the STM32 series. Pins 25 and 27 of the main controller U8 are connected to two photoelectric switches 600 respectively, and pins 61 and 62 are connected to the motor drive circuit to output PWM control signals to the motor drive circuit. Pins 53 to 57 are connected to the key circuit, and pins 51, 52, 58 and 59 are connected to the communication circuit. Figure 7 In this embodiment, the communication circuit adopts RS232 serial communication protocol and is composed of a communication interface chip of model MAX3232E and its peripheral circuits.

[0037] Reference Figures 8 to 10 In this embodiment, the power supply circuit includes a rectifier filter circuit, a first step-down circuit, and a second step-down circuit connected in sequence. The rectifier filter circuit includes a common mode inductor of model ACM7060, a fuse F3, and a Schottky rectifier D3 of model STP6M100DEE, which rectifies and filters the input 12V voltage and then transmits it to the motor drive circuit. The first step-down circuit includes a power management chip U7 of model TPS5430 and its peripheral circuits, which converts the 12V voltage output by the rectifier filter circuit into a 5V voltage. The second step-down circuit includes a voltage stabilizing chip of model AZ1117 and its peripheral circuits, which converts the 5V voltage output by the first step-down circuit into a 3.3V voltage and supplies power to each chip in the control circuit.

[0038] Reference Fig.11 In this embodiment, the motor driving circuit uses a motor 410 driving chip U2 of model DRV8220DSGR, which can drive two motors 410 with a single chip. Fig.12 In this embodiment, the current feedback circuit includes a current sampling circuit composed of a sampling resistor R15 and a capacitor C15, and a signal amplification circuit composed of an operational amplifier U3 and a plurality of resistors. The current sampling circuit is connected to the GND pin of the motor 410 driving chip U2 to sample the current of the motor 410, and the sampled current is amplified by the signal amplification circuit and transmitted to the 14th pin of the main controller U8.

[0039] It should be noted that in the description of the present invention, if there are any orientation descriptions, such as up, down, front, back, left, right, etc., the orientations or positional relationships indicated are all based on the orientations or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operated in a specific orientation, and cannot be understood as a limitation on the present invention.

[0040] In the description of the present invention, "several" means one or more, "more" means two or more, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used to distinguish the technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0041] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0042] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A multi-spectral filtering device, characterized in that: The invention comprises a control circuit, a housing (100), a first filter wheel (200), a first rotation drive mechanism (400), a second filter wheel (300) and a second rotation drive mechanism (500); the first filter wheel (200) and the second filter wheel (300) are both rotatably arranged in the housing (100); an observation window (110) is arranged on the upper and lower surfaces of the housing (100); the observation window (110) on the upper surface overlaps with the observation window (110) on the lower surface; the first filter wheel (200) and the second filter wheel (300) are both provided with a plurality of filters (210) having different passing bands; the center of the filter (210) on the first filter wheel (200) is axially spaced from the center of the filter (210) to the center of the filter (210) on the first filter wheel (200); ), the distance between the center of the filter (210) on the second filter wheel (300) and the rotation center of the second filter wheel (300) is the same, the distance between the center of the filter (210) on the second filter wheel (300) and the rotation center of the second filter wheel (300) is the same, the first rotation drive mechanism (400) is used to drive the first filter wheel (200) to rotate so that the filters (210) on the first filter wheel (200) can overlap with the observation window (110) one by one, the second rotation drive mechanism (500) is used to drive the second filter wheel (300) to rotate so that the filters (210) on the second filter wheel (300) can overlap with the observation window (110) one by one, and the first rotation drive mechanism (400) and the second rotation drive mechanism (500) are both electrically connected to the control circuit.

2. The multi-spectral filtering device according to claim 1, characterized in that: The rotation centers of the first filter wheel (200) and the second filter wheel (300) coincide with each other.

3. The multi-spectral filtering device according to claim 2, characterized in that: The first filter wheel (200) and the second filter wheel (300) have the same structure; a rotating shaft seat (220) is arranged on the upper surface of the first filter wheel (200) and the second filter wheel (300); and a rotating shaft (230) matching the rotating shaft seat (220) is arranged on the lower surface of the first filter wheel (200) and the second filter wheel (300).

4. The multi-spectral filtering device according to claim 3, characterized in that: The rotation connection between the second filter wheel (300) and the housing (100), and the rotation connection between the first filter wheel (200) and the second filter wheel (300) are both made of self-lubricating engineering plastics.

5. The multi-spectral filtering device according to claim 1, characterized in that: Teeth are arranged on the circumferential surfaces of the first filter wheel (200) and the second filter wheel (300); the first rotation drive mechanism (400) and the second rotation drive mechanism (500) both comprise a motor (410), an encoder and a transmission gear (420); the transmission gear (420) and the encoder are both connected to the output shaft of the motor (410); the transmission gear (420) meshes with the teeth on the corresponding first filter wheel (200) or the second filter wheel (300); and the motor (410) and the encoder are electrically connected to the control circuit.

6. The multi-spectral filtering device according to claim 5, characterized in that: The first filter wheel (200) and the second filter wheel (300) are both provided with baffles (240), and the housing (100) is provided with two photoelectric switches (600) for respectively detecting the positions of the baffles (240) on the first filter wheel (200) and the baffles (240) on the second filter wheel (300), and the two photoelectric switches (600) are both electrically connected to the control circuit.

7. The multi-spectral filtering device according to claim 5, characterized in that: The control circuit comprises a main controller, a power supply circuit, a motor drive circuit, a key circuit and a communication circuit. The output ends of the key circuit and the communication circuit are both electrically connected to the main controller. The input end of the motor drive circuit is electrically connected to the main controller. The output end of the motor drive circuit is electrically connected to the motors (410) in the first rotation drive mechanism (400) and the second rotation drive mechanism (500). The power supply circuit is used to supply power to the control circuit.

8. The multi-spectral filtering device according to claim 7, characterized in that: The control circuit further comprises a current feedback circuit, wherein an input end of the current feedback circuit is electrically connected to the motor (410) in the first rotation drive mechanism (400) and the second rotation drive mechanism (500), and an output end of the current feedback circuit is electrically connected to the main controller.

9. The multi-spectral filtering device according to claim 7, characterized in that: The power supply circuit includes a rectifying and filtering circuit, a first buck circuit and a second buck circuit connected in sequence.

10. The multi-spectral filtering device according to claim 1, characterized in that: The optical filters (210) on one of the first filter wheel (200) and the second filter wheel (300) are both high-pass filters, and the optical filters (210) on the other of the first filter wheel (200) and the second filter wheel (300) are both low-pass filters.

Images