Optical grating capable of resisting light interference
By introducing an optical filtering device into the safety grating, the impact of high-intensity near-infrared interference light on the safety grating is solved, and stable and safe protection is achieved in laser cutting scenarios, ensuring the effective operation of the safety grating.
Patent Information
- Application Number
- CN202422286846.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-18
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2034-09-18
AI Technical Summary
Existing safety gratings are prone to false alarms or failures under high-intensity near-infrared interference light sources, and cannot effectively protect personal safety in scenarios such as laser welding and laser cutting.
A grating that is anti-light interference is designed, and an optical filtering device is used to achieve effective filtering of interfering light through a combination of structural aperture, receiving lens and circuit board.
It realizes effective suppression of the interfering light of carbon dioxide laser light source in laser cutting scenarios, ensures the stable application of safety gratings, avoids false alarms, and improves the reliability of safety protection.
Smart Images
Figure CN223137588U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of gratings, and particularly to a grating resistant to optical interference. Background Art
[0002] A safety grating, namely an optoelectronic safety protection device. In modern factories, people and machines work together. Some potentially dangerous mechanical equipment, such as stamping machines, shearing equipment, metal cutting equipment, automated assembly lines, automated welding lines, mechanical transmission and handling equipment, and dangerous areas (toxic, high-pressure, high-temperature, etc.), are likely to cause personal injuries to operators. The safety grating emits infrared rays to generate a protection light curtain. When the light curtain is blocked, the device emits a light-shielding signal to control the potentially dangerous mechanical equipment to stop working and avoid safety accidents.
[0003] In some industrial application scenarios, such as laser welding and laser cutting, high-power laser light sources are used, which pose relatively high risks. It is also desirable to select a safety grating as a safety protection device. However, because high-power laser light sources will generate intense interference light in the near-infrared band in space during operation, which affects the safety grating, resulting in false alarms or malfunctions of the safety grating, so that the safety grating cannot be used normally in scenarios with strong interference light sources such as laser welding and laser cutting.
[0004] It can be imagined that in some application scenarios, by reducing the sensitivity of the receiving device of the safety grating, the application in some scenarios with relatively weak interference light source power can be solved. However, this method will also reduce the receiving effect on its own transmitter, resulting in a decrease in the protection distance. Therefore, in view of such application pain points, a new technical solution is urgently needed to achieve immunity to near-infrared interference light sources in industrial scenarios without reducing its own receiving effect, and thus achieve reliable safety protection for such working scenarios. Summary of the Invention
[0005] The purpose of the utility model is to provide a grating resistant to optical interference. The transmittance of the optical filtering device for wavelengths of 850 nm and 940 nm is greater than 99%, and the transmittance of the optical filtering device for wavelengths in the interference light range of 1064 nm ± 50 nm is less than 0.1%, so that the grating resistant to optical interference of the present application can achieve the effect of resisting optical interference.
[0006] To this end, the present utility model provides a grating resistant to optical interference, which includes a plurality of receiving units connected in series in sequence. The receiving unit includes: a structural diaphragm, on which a diaphragm hole is provided, and an optical filtering device is installed in the diaphragm hole; a receiving lens, which is snap-fitted at one end of the diaphragm hole; a circuit board, which is fixed to the structural diaphragm; a receiving device is installed on the circuit board, and the receiving device is located at the other end of the diaphragm hole; the centers of the receiving device, the optical filtering device, and the receiving lens are located on the same straight line.
[0007] In an embodiment of the present application, the optical filtering device includes optical glass, and a band-pass film layer is provided on one side of the optical glass. The band-pass film layer includes multiple layers of first refractive layers and multiple layers of second refractive layers stacked alternately; the refractive index of the first refractive layer is greater than that of the second refractive layer.
[0008] In an embodiment of the present application, a band-stop film layer is provided on the other side of the optical glass. The band-stop film layer includes multiple layers of third refractive layers and multiple layers of fourth refractive layers stacked alternately; the refractive index of the third refractive layer is greater than that of the fourth refractive layer.
[0009] In an embodiment of the present application, the transmittance of the optical filtering device for wavelengths of 850 nm and 940 nm is greater than 99%.
[0010] In an embodiment of the present application, the transmittance of the optical filtering device for a wavelength of 1064 nm is less than 0.1%.
[0011] In an embodiment of the present application, the receiving lens is provided with a snap-fitting step portion, and the snap-fitting step portion is snap-fitted at one end of the diaphragm hole.
[0012] Compared with the prior art, the advantages and positive effects of the present utility model are as follows: The present utility model provides an anti-light-interference grating, which includes a plurality of receiving units connected in series in sequence. Each receiving unit includes: a structural diaphragm, on which there is a diaphragm hole, and an optical filtering device is installed in the diaphragm hole; a receiving lens, which is snap-fitted at one end of the diaphragm hole; a circuit board, which is fixed to the structural diaphragm; a receiving device is installed on the circuit board, and the receiving device is located at the other end of the diaphragm hole; the centers of the receiving device, the optical filtering device, and the receiving lens are on the same straight line. The optical filtering device has a transmittance greater than 99% for wavelengths of 850 nm and 940 nm, and the transmittance of the optical filtering device for the interference light in the wavelength range of 1064 nm ± 50 nm is less than 0.1%. Thus, the anti-light-interference grating of the present application can achieve the effect of anti-light interference; the anti-light-interference grating of the present application can have a good suppression effect on the interference light model of the carbon dioxide laser light source used in the laser cutting scenario, and can realize the stable application of the safety grating against light interference.
[0013] After reading the specific embodiments of the present utility model in conjunction with the accompanying drawings, other features and advantages of the present utility model will become clearer. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 is a cross-sectional schematic diagram of an embodiment of the anti-light-interference grating of the present utility model;
[0015] Figure 2 is a partial cross-sectional schematic diagram of an embodiment of the structural diaphragm of the present utility model;
[0016] Figure 3 is a structural schematic diagram of an embodiment of the optical filtering device of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0017] In order to make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the following will further elaborate on the present utility model in detail in conjunction with the accompanying drawings and embodiments.
[0018] As Figures 1 - 3 shown, the anti-light-interference grating of the present utility model includes a plurality of series-connected receiving units. Each receiving unit includes: a structural diaphragm 10, on which there is a diaphragm hole 11, and an optical filtering device 20 is installed in the diaphragm hole 11; a receiving lens 30, which is installed at one end of the diaphragm hole 11; a circuit board 40, which is fixed to the structural diaphragm 10; a receiving device 50 is installed on the circuit board 40, and the receiving device 50 is located at the other end of the diaphragm hole 11; the centers of the receiving device 50, the optical filtering device 20, and the receiving lens 30 are on the same straight line.
[0019] The optical filtering device 20 includes an optical glass 21, which can be a homogeneous optical glass commonly used in this technical field and has good optical transmission characteristics. The optical glass 21 can be sapphire glass, quartz glass, flint glass, crown glass, borosodium glass, aluminosilicate glass, etc., and no specific limitation is made here.
[0020] The thickness of the optical glass 21 can be 0.3 mm - 0.8 mm, preferably 0.5 mm, and no specific limitation is made here.
[0021] A band-pass film layer is provided on one side of the optical glass 21. The band-pass film layer can be formed on one side of the optical glass 21 by evaporation coating process or sputtering process, and no specific limitation is made here.
[0022] The band-pass film layer includes multiple layers of first refractive layers 22 and multiple layers of second refractive layers 23 stacked alternately. The refractive index of the first refractive layer 22 is greater than that of the second refractive layer 23.
[0023] The number of layers of the first refractive layer 22 can be 1 layer, 2 layers, 3 layers or multiple layers, and no specific limitation is made here.
[0024] The number of layers of the second refractive layer 23 can be 1 layer, 2 layers, 3 layers or multiple layers, and no specific limitation is made here.
[0025] The thickness of the first refractive layer 22 can be 1 - 5 μm, and no specific limitation is made here.
[0026] The thickness of the second refractive layer 23 can be 1 - 5 μm, and no specific limitation is made here.
[0027] The function of the band-pass film layer is: according to the wavelength range selected by the transmitter, it can enhance the transmission of the optimal working wavelength range of the receiving device, so that the optical filtering device 20 has a transmittance greater than 99% for the wavelengths of 850 nm and 940 nm.
[0028] A band-stop film layer is provided on one side of the optical glass 21. The band-stop film layer can be formed on one side of the optical glass 21 by evaporation coating process or sputtering process, and no specific limitation is made here.
[0029] The band-stop film layer includes multiple layers of third refractive layers 24 and multiple layers of fourth refractive layers 25 stacked alternately. The refractive index of the third refractive layer 24 is greater than that of the fourth refractive layer 25.
[0030] The number of layers of the third refractive layer 24 can be 1 layer, 2 layers, 3 layers or multiple layers, and no specific limitation is made here.
[0031] The number of layers of the fourth refractive layer 25 can be 1 layer, 2 layers, 3 layers or multiple layers, and no specific limitation is made here.
[0032] The thickness of the third refractive layer 24 can be 1 - 5 μm, and no specific limitation is imposed herein.
[0033] The thickness of the fourth refractive layer 25 can be 1 - 5 μm, and no specific limitation is imposed herein.
[0034] The function of the band-stop film layer is as follows: according to the interference wavelength range of the interfering light, it can transmit and block the wavelength range that affects the normal reception of the receiving device, so that the optical filtering device 20 has a transmittance of less than 0.1% for the wavelength of 1064 nm ± 50 nm.
[0035] The optical filtering device 20 has a transmittance greater than 99% for the wavelengths of 850 nm and 940 nm, and the optical filtering device 20 has a transmittance of less than 0.1% for the interfering light in the wavelength range of 1064 nm ± 50 nm, so that the anti-light-interference grating of the present application can achieve the anti-light-interference effect; the anti-light-interference grating of the present application can have a good suppression effect on the interference light model of the carbon dioxide laser light source used in the laser cutting scenario, and can achieve the stable application of the safety grating against light interference.
[0036] The structural diaphragm 10 is the structural main body of the receiving unit, and a diaphragm hole 11 is provided in the middle part thereof. The diaphragm hole 11 can reduce the incidence of stray light at large angles on the receiving device 50 and improve the signal-to-noise ratio at the receiving end.
[0037] The main function of the receiving lens 30 is to focus and irradiate the parallel incident light on the surface of the receiving device 50 to improve the receiving efficiency. The receiving lens 30 is provided with a snap-in step portion 31, and the snap-in step portion 31 is snapped onto one end of the diaphragm hole 11. The receiving lens 30 can also be fixed in the diaphragm hole 11 by other common methods in the art, and no specific limitation is imposed herein.
[0038] The main function of the receiving device 50 is to convert the incident optical signal into an electrical signal and then transmit it to the logic processing unit of the grating through the wires laid on the circuit board 40.
[0039] The receiving device 50 can be fixed on the circuit board 40 by means of mounting or soldering, and no specific limitation is imposed herein.
[0040] The circuit board 40 is the carrier of the grating circuit part. In this embodiment, its main function is to carry the receiving device 50, and the circuit board 40 is positioned and fixed on the receiving diaphragm 10. The circuit board 40 and the structural diaphragm 10 can be fixedly connected by bolt connection or snap connection, and no specific limitation is imposed herein.
[0041] The main function of the optical filtering device 20 is to perform wavelength resolution and processing on the light rays that are converged by the receiving lens 30 and pass through the aperture 11. The light rays that meet the passing characteristics can normally penetrate the optical filtering device 20 and reach the receiving device 50 through the aperture 11; the light rays that do not meet the passing characteristics cannot penetrate the optical filtering device 20 and are reflected or absorbed and dissipated, and cannot reach the receiving device 50.
[0042] The optical filtering device 20 of the present application is a type of optical device, and different optical designs can achieve different effects such as anti-reflection or blocking for different wavelength ranges.
[0043] In the present application, an optical filtering device 20 is added inside the structural aperture 10 of the safety grating, which can reduce the probability of light rays with a wavelength of 1064 nm ± 50 nm entering the receiving device 50, thereby reducing the probability of the receiving device 50 being interfered by light and achieving the effect of anti-light interference.
[0044] The optical filtering device 20 can be fixed in the aperture 11 by bonding, and no specific limitation is made here. In the present application, an installation step 12 can be provided in the aperture 11, and the optical filtering device 20 is installed on the installation step 12.
[0045] As Figure 2 shown, the top of the aperture 11 is open, and the receiving lens 30 is installed at the top opening of the aperture 11. A bottom plate 12 is provided at the bottom of the aperture 11, and a through hole 13 is provided on the bottom plate 12; the optical filtering device 20 is installed on the bottom plate 12, and the optical filtering device 20 corresponds to the through hole 13. The receiving device 50 extends into the through hole 13 and corresponds to the optical filtering device 20.
[0046] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, for those of ordinary skill in the art, it is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions required to be protected by the present invention.
Claims
1. A grating resistant to optical interference, characterized in that: It includes a plurality of receiving units connected in series in sequence, and the receiving unit includes: A structural diaphragm, on which there is a diaphragm hole, and an optical filtering device is installed in the diaphragm hole; A receiving lens, which is snap-fitted at one end of the diaphragm hole; A circuit board, which is fixed to the structural diaphragm; a receiving device is installed on the circuit board, and the receiving device is located at the other end of the diaphragm hole; The centers of the receiving device, the optical filtering device, and the receiving lens are on the same straight line.
2. The grating resistant to optical interference according to claim 1, characterized in that: The optical filtering device includes optical glass, and a band-pass film layer is provided on one side of the optical glass. The band-pass film layer includes multiple layers of first refractive layers and multiple layers of second refractive layers stacked alternately; The refractive index of the first refractive layer is greater than that of the second refractive layer.
3. The grating resistant to optical interference according to claim 2, characterized in that: A band-stop film layer is provided on the other side of the optical glass. The band-stop film layer includes multiple layers of third refractive layers and multiple layers of fourth refractive layers stacked alternately; The refractive index of the third refractive layer is greater than that of the fourth refractive layer.
4. The grating resistant to optical interference according to claim 1, characterized in that: The transmittance of the optical filtering device for wavelengths of 850 nm and 940 nm is greater than 99%.
5. The grating resistant to optical interference according to claim 1, characterized in that: The transmittance of the optical filtering device for a wavelength of 1064 nm is less than 0.1%.
6. The grating resistant to optical interference according to claim 1, characterized in that: The receiving lens is provided with a snap-fitting step portion, and the snap-fitting step portion is snap-fitted at one end of the diaphragm hole.