Photodiode responsivity testing device
By designing a photodiode responsiveness test device, the photodiode responsiveness test error and environmental adjustment flexibility are solved by using incident filter, spectroscopy and exit filter components, and high-precision and flexible photodiode responsiveness test are achieved.
Patent Information
- Application Number
- CN202421719868.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-19
- Publication Date
- 2025-07-01
- Estimated Expiration
- 2034-07-19
AI Technical Summary
There are errors in existing photodiode responsiveness tests, and the test environment adjustment flexibility is poor, which cannot meet the specific test requirements of different wavelengths of light and external bias voltages.
A photodiode responsiveness test device is designed, including a light source component, an incident filter component, a spectrometer, an exit filter component, an ammeter and a photodiode. The stray light is filtered out through the incident filter component, and the spectrometer forms outgoing light of different wavelengths, the exit filter component filters out stray light, and the ammeter is biased in series to provide an external bias voltage to meet a specific test environment.
It improves the accuracy and environmental adjustment flexibility of photodiode responsiveness testing, ensures that high-purity light is accurately illuminated to the photosensitive surface, meets the testing needs of different wavelengths and external biases, and simplifies testing operations.
Smart Images
Figure CN223051449U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to optical testing equipment, in particular to a test device for the responsivity of a photosensitive diode. Background Art
[0002] A photosensitive diode can respond to light within a specific wavelength range and convert the light signal into an electrical signal for output. The responsivity of the photosensitive diode determines the timeliness and accuracy of the output electrical signal. Currently, the method for testing the responsivity performance of a photosensitive diode is to irradiate the photosensitive diode with light and measure the output current value of the photosensitive diode through an ammeter.
[0003] Different angles of light irradiation will cause the test results of the responsivity of the photosensitive diode to be correspondingly different, which easily leads to errors in the test results. At the same time, the existing test devices cannot meet the requirements of specific test environments such as testing under different wavelengths of light and external bias voltages, and the flexibility of adjusting the test environment is poor. Therefore, it is necessary to provide a test device for the responsivity of a photosensitive diode, which can solve the problems of errors in the test results of the responsivity of the photosensitive diode and poor flexibility in adjusting the test environment in the prior art. Summary of the Invention
[0004] The purpose of the utility model is to provide a test device for the responsivity of a photosensitive diode, which can solve the problems of errors in the test results of the responsivity of the photosensitive diode and poor flexibility in adjusting the test environment in the prior art.
[0005] The utility model is implemented as follows:
[0006] A test device for the responsivity of a photosensitive diode includes a light source assembly, an incident filter assembly, a beam splitting assembly, an exit filter assembly, an ammeter, a photosensitive diode, and a test stand. The incident filter assembly is arranged between the light source assembly and the beam splitting assembly, so that the light of the light source assembly passes through the incident filter assembly and irradiates on the beam splitting assembly, and forms exit light of different wavelengths. The photosensitive diode is arranged on the test stand, and the ammeter is connected in series with the photosensitive diode. The exit filter assembly is arranged between the beam splitting assembly and the photosensitive diode, so that the exit light irradiates on the photosensitive diode after being filtered by the exit filter assembly.
[0007] The light source assembly includes a tungsten halogen lamp and a first spherical mirror. The tungsten halogen lamp is arranged facing the first spherical mirror, and the first spherical mirror is arranged facing the incident filter assembly, so that the light of the tungsten halogen lamp is reflected by the first spherical mirror to the incident filter assembly.
[0008] The incident filter assembly includes a filter, an incident slit, and a plane mirror. The filter, the incident slit, and the plane mirror are sequentially arranged at intervals along the direction of the light reflected by the first spherical mirror. The plane mirror is arranged facing the beam splitting assembly, so that the light enters the beam splitting assembly through the plane mirror.
[0009] The described light splitting component includes a second spherical mirror and a grating. An incident area and an exit area are formed on the second spherical mirror. The plane mirror is arranged facing the incident area of the second spherical mirror, and the exit area of the second spherical mirror faces the exit filter component. The second spherical mirror is arranged in parallel with the grating, and the grating is located between the incident area and the exit area of the second spherical mirror.
[0010] The described grating is arranged collinearly with the incident filter component, and the second spherical mirror is located beside the grating, so that a broken-line-shaped light path is formed among the plane mirror, the incident area of the second spherical mirror, the grating, the exit area of the second spherical mirror, and the exit filter component.
[0011] The described exit filter component includes an exit slit and a lens. The exit area of the second spherical mirror, the exit slit, the lens, and the photosensitive surface of the photosensitive diode are arranged collinearly along the direction of the exit light.
[0012] The described ammeter is connected in series with a bias power supply, and the series-connected ammeter and bias power supply are connected in series with the photosensitive diode.
[0013] The described photosensitive diode includes a calibrated photosensitive diode and a photosensitive diode to be measured.
[0014] Compared with the prior art, the present utility model has the following beneficial effects:
[0015] 1. Since the present utility model is provided with an incident filter component, a light splitting component, and an exit filter component, the incident light is filtered twice by the incident filter component to remove stray light and ensure the high purity of the incident light. The light splitting component uses the autocollimation arrangement technology to make the incident light form exit lights of different wavelengths. The exit lights are filtered by the exit filter component, so that the high-purity exit lights accurately irradiate the photosensitive surface of the photosensitive diode, avoiding the influence of stray light and light angle on the test result, which is beneficial to improving the test accuracy of the photosensitive diode responsivity.
[0016] 2. Since the present utility model is provided with a grating and a bias power supply, the incident light is diffracted by the grating to form exit lights of different wavelengths, which can meet the test requirements of the photocurrent of the photosensitive diode under different wavelength light conditions. At the same time, by applying an external bias voltage through different bias power supplies, the specific test environment requirements can be met, and the adjustment flexibility of the test environment is high. Description of the Drawings
[0017] Figure 1 It is the front view of the photosensitive diode responsivity test device of the present utility model, and the arrow direction in the figure is the light direction.
[0018] In the figure, 1 is a tungsten halogen lamp, 2 is a first spherical mirror, 3 is a filter, 4 is an incident slit, 5 is a plane mirror, 6 is a spherical mirror, 7 is a grating, 8 is an exit slit, 9 is a lens, 10 is an ammeter, 11 is a bias power supply, 12 is a photodiode, and 13 is a test stand. Specific embodiments
[0019] The present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.
[0020] Please refer to the attached Figure 1 , a photodiode responsivity test device, comprising a light source assembly, an incident light filtering assembly, a light splitting assembly, an exit light filtering assembly, an ammeter 10, a photodiode 12, and a test stand 13; the incident light filtering assembly is arranged between the light source assembly and the light splitting assembly, enabling the light of the light source assembly to pass through the incident light filtering assembly and irradiate onto the light splitting assembly, and forming exit light of different wavelengths; the photodiode 12 is arranged on the test stand 13, and the ammeter 10 is connected in series with the photodiode 12; the exit light filtering assembly is arranged between the light splitting assembly and the photodiode 12, enabling the exit light to be filtered by the exit light filtering assembly and then irradiate onto the photodiode 12.
[0021] The light source assembly is used to provide incident light. The incident light filtering assembly can filter the incident light, removing stray light, etc., and improving the purity of the incident light. The light splitting assembly is used to split the incident light into incident light of different wavelengths, thereby meeting the requirement for measuring the photocurrent of the photodiode 12 under the condition of incident light of different wavelengths. The exit light filtering assembly is used to filter the split exit light, removing stray light, etc., and improving the purity of the exit light. The test stand 13 is used to fix the photodiode 12, thereby ensuring that the high-purity exit light can accurately converge onto the photosensitive surface of the photodiode 12, which is beneficial to improving the test accuracy of the photodiode responsivity.
[0022] The described light source assembly includes a tungsten halogen lamp 1 and a first spherical mirror 2. The tungsten halogen lamp 1 is arranged facing the first spherical mirror 2, and the first spherical mirror 2 is arranged facing the incident light filtering assembly, enabling the light of the tungsten halogen lamp 1 to be reflected by the first spherical mirror 2 and irradiate onto the incident light filtering assembly.
[0023] The tungsten halogen lamp 1 is used to provide an initial light source, and the first spherical mirror 2 is used to converge the initial light source onto the incident light filtering assembly.
[0024] The described incident light filtering assembly includes a filter 3, an incident slit 4, and a plane mirror 5; the filter 3, the incident slit 4, and the plane mirror 5 are sequentially arranged at intervals along the direction of the light reflected by the first spherical mirror 2, and the plane mirror 5 is arranged facing the light splitting assembly, enabling the light to enter the light splitting assembly through the plane mirror 5.
[0025] The filter 3 can be used to first filter the light converged by the first spherical mirror 2. The slit width of the incident slit 4 can be adaptively adjusted according to actual filtering requirements for secondarily filtering the light and removing stray light to form incident light of higher purity. The plane mirror 5 is used to converge the filtered incident light to the spectroscopic component.
[0026] The described spectroscopic component includes a second spherical mirror 6 and a grating 7. An incident area and an exit area are formed on the second spherical mirror 6. The plane mirror 5 is arranged facing the incident area of the second spherical mirror 6, and the exit area of the second spherical mirror 6 is facing the exit filter component. The second spherical mirror 6 and the grating 7 are arranged in parallel, and the grating 7 is located between the incident area and the exit area of the second spherical mirror 6.
[0027] The incident area of the second spherical mirror 6 is used to receive the incident light and reflect it to the grating 7. The diffraction effect of the grating 7 is used to diffract the incident light into light of different wavelengths and converge it to the exit filter component through the exit area of the second spherical mirror 6.
[0028] The described grating 7 and the incident filter component are arranged collinearly. The second spherical mirror 6 is located beside the grating 7, forming a zigzag light path among the plane mirror 5, the incident area of the second spherical mirror 6, the grating 7, the exit area of the second spherical mirror 6, and the exit filter component, with high structural integration and a smaller volume for the entire testing device.
[0029] The described exit filter component includes an exit slit 8 and a lens 9. The exit area of the second spherical mirror 6, the exit slit 8, the lens 9, and the photosensitive surface of the photosensitive diode 12 are arranged collinearly along the direction of the exit light.
[0030] Preferably, the grating 7 is arranged in a self - collimating manner, capable of adjusting the wavelength range between 200 - 1100 nanometers to meet different test wavelength requirements and ensuring that the exit light is stably and accurately positioned on the photosensitive surface of the photosensitive diode 12 through the exit slit 8 and the lens 9. By splitting the light through the grating 7 and filtering out stray light through the exit slit 8, the exit light can maintain high purity when converged to the photosensitive diode 12 through the lens 9, optimizing the light quality.
[0031] Preferably, the lens 9 can be a precision lens at the micron level, enabling the spot diameter of the emitted light to reach the micron level and allowing for the testing of photosensitive diodes 12 with a smaller photosensitive surface area.
[0032] The described ammeter 10 is connected in series with the bias power supply 11, and the series - connected ammeter 10 and bias power supply 11 are connected in series with the photosensitive diode 12.
[0033] The bias power supply 11 can provide an external bias voltage for the photosensitive diode 12, and different bias voltages can be adjusted to meet the requirements of specific testing environments.
[0034] The described photosensitive diode 12 includes a calibrated photosensitive diode and a photosensitive diode to be measured.
[0035] The responsivity of the calibrated photosensitive diode is known. By testing the photocurrent of the calibrated photosensitive diode, it is used to provide basic test data for the responsivity test of the photosensitive diode to be measured, and can make the test operation simpler and more convenient while ensuring the accuracy of the responsivity test result of the photosensitive diode to be measured.
[0036] Please refer to the appendix Figure 1 , the test process and working principle of the present utility model are as follows:
[0037] The halogen tungsten lamp 1 irradiates light onto the first spherical mirror 2. The first spherical mirror 2 focuses the light of the halogen tungsten lamp 1 onto the entrance slit 4 after filtering through the filter 3. The incident light is converged through the entrance slit 4 and then irradiates onto the plane mirror 5, and is refocused onto the incident area on the second spherical mirror 6 through the plane mirror 5. The incident area of the second spherical mirror 6 reflects the light to the grating 7, and the light is dispersed by the grating 7 to form outgoing light of different wavelengths. The outgoing light is filtered out of stray light when passing through the exit slit 8, and finally converges onto the photosensitive surface of the photosensitive diode 12 through the lens 9.
[0038] During the test, first use a calibrated photosensitive diode (with a responsivity of S) and fix it on the test stand 13. By using the different wavelengths of light formed by the dispersion of the grating 7 in combination with the calibrated photosensitive diode, measure the photocurrent I1 at different wavelengths. The photocurrent I1 can be read and recorded through the ammeter 10.
[0039] Then replace the photosensitive diode to be measured and fix it on the test stand 13, replacing the calibrated photosensitive diode, and measure its photocurrent I2 at the same wavelength. The measurement method is the same as that of the photocurrent I1 of the calibrated photosensitive diode, which will not be elaborated here.
[0040] After the measurement is completed, calculate the responsivity of the photosensitive diode to be measured through the formula I2 / (I1 / S), so as to obtain the responsivity curve of the photosensitive diode to be measured. Its test method and calculation process are simple, and the test result is accurate, and it can be applied to the responsivity curve test of various photosensitive devices.
[0041] During the test process, if it is necessary to adjust the test conditions, that is, it is necessary to increase an external bias voltage, a corresponding bias power supply 11 can be connected in series on the ammeter 10 according to the test requirements, which can provide different test conditions and has high flexibility in adjusting the test environment.
[0042] The above is only a preferred embodiment of the present utility model and is not used to limit the protection scope of the present utility model. Therefore, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.
Claims
1. A photodiode responsivity test device, characterized in that: The invention comprises a light source component, an incident light filter component, a light splitting component, an exit light filter component, an ammeter (10), a photosensitive diode (12) and a test frame (13); the incident light filter component is arranged between the light source component and the light splitting component, so that the light of the light source component passes through the incident light filter component and irradiates the light splitting component, and forms exit light of different wavelengths; the photosensitive diode (12) is arranged on the test frame (13), and the ammeter (10) is connected in series to the photosensitive diode (12); and the exit light filter component is arranged between the light splitting component and the photosensitive diode (12), so that the exit light is filtered by the exit light filter component and then irradiates the photosensitive diode (12).
2. The photodiode responsivity test device according to claim 1, characterized in that: The light source assembly comprises a tungsten halogen lamp (1) and a first spherical mirror (2); the tungsten halogen lamp (1) is arranged facing the first spherical mirror (2), and the first spherical mirror (2) is arranged facing the incident light filtering assembly, so that light from the tungsten halogen lamp (1) is reflected to the incident light filtering assembly through the first spherical mirror (2).
3. The photodiode responsivity testing device according to claim 2, characterized in that: The incident light filtering component comprises a filter (3), an incident slit (4) and a plane mirror (5); the filter (3), the incident slit (4) and the plane mirror (5) are arranged in sequence and spaced apart along the direction in which the first spherical mirror (2) reflects the light, and the plane mirror (5) is arranged facing the light splitting component so that the light passes through the plane mirror (5) and is incident on the light splitting component.
4. The photodiode responsivity testing device according to claim 3, characterized in that: The light splitting component comprises a second spherical mirror (6) and a grating (7); an incident area and an exit area are formed on the second spherical mirror (6); the plane mirror (5) is arranged facing the incident area of the second spherical mirror (6); and the exit area of the second spherical mirror (6) is arranged facing the exit filter component; the second spherical mirror (6) and the grating (7) are arranged in parallel, and the grating (7) is located between the incident area and the exit area of the second spherical mirror (6).
5. The photodiode responsivity testing device according to claim 4, characterized in that: The grating (7) and the incident light filtering component are arranged in a colinear manner, and the second spherical mirror (6) is located beside the grating (7), so that a broken line of light is formed between the plane mirror (5), the incident area of the second spherical mirror (6), the grating (7), the exit area of the second spherical mirror (6) and the exit light filtering component.
6. The device for testing the responsivity of a photodiode according to claim 4 or 5, characterized in that: The exit filter assembly comprises an exit slit (8) and a lens (9), and the exit area of the second spherical mirror (6), the exit slit (8), the lens (9) and the photosensitive surface of the photodiode (12) are collinearly arranged along the direction of the exit light.
7. The photodiode responsivity testing device according to claim 1, characterized in that: The ammeter (10) is connected in series with a bias power supply (11), and the series-connected ammeter (10) and the bias power supply (11) are connected in series with a photosensitive diode (12).
8. The device for testing the responsivity of a photodiode according to claim 1 or 7, characterized in that: The photosensitive diode (12) comprises a calibrated photosensitive diode and a photosensitive diode to be tested.