A high-precision, wide dynamic range, and high uniformity electric diaphragm

Abstract

This invention provides a high-precision, wide-dynamic-range, and highly uniform motorized diaphragm. This diaphragm controls the transmitted radiant flux between integrating spheres. It ensures high uniformity, dynamic adjustability over a wide range, and high repeatability. When fully closed, light leakage is maintained at a radiant brightness output level of one millionth of that in the fully open state. This invention meets the performance requirements of highly uniform low-light radiation sources.

Description

Technical Field

[0001] The invention belongs to the field of diaphragms, and in particular relates to a high-precision, wide-dynamic-range, and high-uniformity electric diaphragm. Background Art

[0002] During the development process, high-precision sensors used in remote sensing require calibration experiments to establish a quantitative relationship between the sensor's received radiance input and its digital output, determining performance parameters such as the sensor's surface uniformity, dynamic range, linearity, stability, and signal-to-noise ratio. Integrating sphere light sources, widely used as uniform diffuse calibration sources, can produce highly stable and uniform radiance output. However, with the deepening of research and application development in various low-light-level remote sensing fields, such as night vision detection, fluorescence imaging, biomedical imaging, and deep space exploration, increasing demand for low-light-level radiation sources has placed even higher performance requirements.

[0003] To meet higher performance requirements, highly uniform low-light radiance sources were developed. These utilize multiple interconnected integrating spheres, which transmit light between them multiple times to improve the uniformity of the light source's output radiance. The connection between the integrating spheres serves as the mounting location for the aperture, which provides dynamic radiance adjustment and high repeatability in highly uniform light sources while maintaining the overall uniformity of irradiance output. Aperture design is a crucial step in the design of highly uniform low-light radiance sources, and its performance significantly impacts the performance of the light source system.

[0004] There is currently little research on motorized apertures in high-uniform low-light radiation sources. The main problems with apertures in this research are as follows:

[0005] 1. Current research on motorized apertures lacks a stray light elimination structure. Because integrating spheres use a Lambertian diffuse light source, the emitted light is not always parallel to the sphere's aperture normal; instead, the majority of the light is concentrated within a ±60° range from the normal. Without a stray light elimination structure or measures, light reflected from within the cavity will affect the uniformity of the aperture's output light, reducing the uniformity of the low-light radiation source.

[0006] 2. The dynamic range of electric aperture adjustment in the current research field is at the level of 4 orders of magnitude (that is, the ratio of maximum radiant brightness output to minimum radiant brightness output is 10000:1), which cannot meet the large dynamic range indicators required by the increasingly high-level low-light remote sensing field.

[0007] 3. In the current research field, it is impossible to quantify the aperture position index with high precision in the electric aperture, and it is impossible to achieve a high repeatability index of the radiant brightness output, which leads to a decrease in the radiant brightness output accuracy of the low-light radiation source in the calibration experiment, resulting in a decrease in the calibration accuracy.

[0008] 4. When the aperture system currently under research is fully closed, a small amount of light leakage occurs near the light exit aperture. This results in a small amount of light output even when the light source is fully closed, limiting the minimum radiance output of the light source, thereby raising the lower limit of the low-light-level radiation source output and failing to meet the lower radiance output requirements of the low-light-level remote sensing field.

[0009] 5. Most of the apertures in the current research field do not have a heat dissipation structure for the temperature control of the motor, and cannot monitor the real-time temperature of the motor, which causes the motor temperature to rise when a high-power light source is output, increases the working error of the motor, and thus reduces the accuracy level of the aperture output radiance.

[0010] 6. Currently, apertures in the research field lack anti-vibration design, making it easy for parts within the aperture system to shift and wobble during equipment transportation and use. This affects the relative position of the light-blocking aperture piece within the aperture system, reducing the repeatability of the aperture for the same radiant flux output. Maintaining highly repeatable radiant flux output is crucial for repeatable radiance or irradiance output of low-light source radiation during calibration experiments, and is a crucial guarantee for high-precision radiation calibration experiments. Summary of the Invention

[0011] To address these issues, the present invention proposes a high-precision, wide-dynamic-range, and highly uniform motorized diaphragm. This diaphragm controls the transmitted radiant flux between integrating spheres, ensuring high uniformity, dynamic adjustability over a wide range, and high repeatability. Furthermore, when fully closed, light leakage is maintained within a range of one millionth of the fully open radiant output level. This meets the performance requirements of low-light, high-uniformity light sources.

[0012] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0013] A high-precision, wide-dynamic-range, and highly uniform electric diaphragm is characterized by comprising a cover plate, a combined diaphragm, a high-precision slide rail, a base, a motor pressure block, a high-precision motor, a TEC cooling block, and heat dissipation fins. The cover plate is connected to an integrating sphere for light input, and the base is connected to the integrating sphere for light input. The cover plate and base are connected by screws, forming the main body of the electric diaphragm. The head portion of the high-precision motor is fixed in a fixing groove on the base, and the head portion of the high-precision motor is fixed by a motor pressure plate. The high-precision slide rail is first installed in the finely machined groove mounting surface of the base, adjusted in position, and then fixed to the base with screws. The combined diaphragm is padded with a metal gasket, fixed to the high-precision slide rail, and finally connected to the push rod of the high-precision motor by screws. The combined aperture piece can make precise movements parallel to the base; the high-precision motor and the four bosses on the base are softly connected by silicone adhesive; the push rod of the high-precision motor makes precise linear motion to control the combined aperture piece to make precise linear motion; the intersection area between the light-shielding hole on the combined aperture piece and the light-emitting hole on the base is changed by linear motion, thereby changing the radiation flux value output by the aperture; the TEC cooling block is fixed to the bottom of the high-precision motor with thermally conductive silicone adhesive, and the other side is connected to the heat sink fin. The temperature sensor of the high-precision motor itself monitors the temperature of the high-precision motor, and the temperature around the high-precision motor is heated or cooled by the TEC cooling block to achieve temperature control of the high-precision motor.

[0014] Furthermore, the aperture cover's light inlet should be designed to be larger than the opening of the integrating sphere. The specific ratio is determined by the ±60° angle of incidence of the integrating sphere's aperture. The design should ensure that the ±60° angle of light emitted from the integrating sphere's aperture is not blocked by the cover's light inlet and surrounding structures. The integrating sphere's aperture should be as close as possible to the aperture.

[0015] In a further solution, the aperture piece is used as a stray light elimination structure, wherein the aperture thickness of the light inlet of the aperture piece should be as small as possible, and there is no structure near the aperture to reflect the incident light from the light inlet. The lower surface roughness of the aperture piece at the bottom of the combined aperture piece should be small, and a certain flatness requirement should be met. The combined aperture piece is an aperture combination structure in which several aperture pieces are stacked up and down at a certain spacing, and the surface is sprayed with a matte paint with a high extinction ratio or subjected to relevant blackening treatment. The aperture piece surface of the combined aperture piece should ensure a high roughness to enhance the adhesion to the matte paint and oxidized blackening substances. Through the superposition effect of multiple planes, the area of ​​the combined aperture piece that absorbs light is effectively increased, and the light absorption capacity of the combined aperture piece is improved, thereby improving the surface uniformity level of the light output by the aperture system.

[0016] In a further embodiment, the cover plate and its inner surface are both sprayed with matte paint or oxidized black. The surface of the cover plate should maintain a high degree of roughness, or be machined with appropriate grooves to increase the area for light absorption. The inner surface roughness of the base should be relatively low and have a certain flatness requirement to ensure that the distance between the combined aperture blade and the base is as small as possible.

[0017] In a further embodiment, the shapes of the cover plate's light entrance aperture, the stray light suppression aperture of the diaphragm, and the base's light exit aperture are symmetrical with respect to the linear motion direction of the high-precision motor. These shapes can be circular, polygonal, exponential, or otherwise, depending on the design requirements. The light entrance aperture of the present invention is preferably circular, while the light shielding aperture and light exit aperture are preferably diamond-shaped. The aperture apertures of the combined diaphragm and diaphragm base decrease in size from top to bottom, with the final base light exit aperture serving as the aperture system's aperture, limiting the maximum output radiation.

[0018] A further solution is to have a retaining groove on the base for the high-precision motor head. This retaining groove does not directly contact the motor head, leaving a certain gap. This gap is filled with an appropriate amount of silicone adhesive. In addition, the base has four bosses on the left and right sides of the high-precision motor, also leaving a certain gap. A suitable amount of silicone adhesive is injected into these gaps to create a soft connection. The principle of the appropriate amount is to ensure that the gap is connected to the high-precision motor. It is not necessary to fill the gap completely; only half of it is sufficient.

[0019] A further solution involves machining a precision-machined grooved mounting surface, slightly larger than the rail and with a specified parallelism tolerance, into the base beneath the high-precision rail. This grooved surface limits the rail's movement angle relative to the high-precision motor pushrod's direction of motion to a very low level, limiting the parallelism and distance between the high-precision rail and the base's top surface. By setting the appropriate distance, the combined aperture blades on the high-precision rail and the base's top surface maintain a very close distance, allowing them to move parallel to each other. In theory, the smaller the distance, the less light leakage.

[0020] The TEC module is preferably installed directly below the high-precision motor. This location is ideal because it's away from the light outlet of the integrating sphere, effectively preventing the absorption of light from the high-power integrating sphere light source, which could affect the TEC module's performance. The heat sink fins, mounted directly below the TEC module, effectively absorb heat released by the hot end. If further heat dissipation is required, an air cooling module can be added to assist with the process.

[0021] In a further solution, the surrounding black part is a multi-level light-absorbing groove, which increases the surface area of ​​light absorption through the groove structure. Spraying matte paint increases surface light absorption, effectively reducing the stray light output of the light output hole.

[0022] The beneficial effects of the present invention are:

[0023] (1) The present invention has designed a stray light elimination structure. Through the base, cover plate and combined aperture plate, it absorbs most of the light diffused by the input integrating sphere, reducing the level of stray light inside the aperture. This improves the surface uniformity of the aperture output irradiance.

[0024] (2) The resolution of the preferred high-precision motor of the present invention is 3.67 μm, and the aperture entrance is designed to be diamond-shaped with a diagonal length of 15 mm, so that the adjustment coefficient of the electric aperture can reach 5.99e -8 The high-precision motor has a repeatability of ±10μm. Combined with high-precision slide rails and related structures, it ensures precise parallel linear motion of the combined aperture pieces, allowing the output flux of the aperture to be dynamically adjustable over a six-level range.

[0025] (3) The linear motor, high-precision slide rail and corresponding structural design adopted in the present invention ensure that the combined aperture plate can make precise linear reciprocating motion in the diagonal direction of the diamond aperture hole and can maintain an angle of 0.03° and a distance of 0.02mm with the upper surface of the base, thereby ensuring the repeatability level of the radiation flux output of the aperture system.

[0026] (4) The present invention incorporates a multi-stage extinction structure within the base, significantly reducing the intensity of light leakage when the aperture is closed. This lowers the lower limit of the aperture's output radiation flux, allowing the aperture system to produce a lower level of radiation flux output. This lower limit of the low-light radiation source's radiation flux output ensures a wider dynamic output range for the low-light radiation source.

[0027] (5) The present invention designs a heat dissipation module that effectively monitors the motor temperature, which can control the high-precision motor temperature within ±0.1°C, ensuring the normal operation of the high-precision motor and improving the repeatability level of the aperture radiation flux output.

[0028] (6) By mechanically fixing the motor head and push rod and using a silicone soft connection, the motor has good adaptability to vibration and impact conditions, thereby ensuring high stability and repeatability of the diaphragm output radiance. This can meet the needs of special use scenarios such as field calibration tasks and long-distance transportation with high vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of a high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to the present invention;

[0030] Figure 2 This is a schematic diagram of the fully open state of the diaphragm system perpendicular to the moving direction of the combined diaphragm piece;

[0031] Figure 3The schematic diagram of the diaphragm system in the closed state parallel to the moving direction of the combined diaphragm blades;

[0032] Figure 4 Schematic diagram of the combined aperture piece;

[0033] Figure 5 Schematic diagram of the base;

[0034] Figure 6 This is the principle diagram of the aperture system's flux output adjustment. DETAILED DESCRIPTION

[0035] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0036] The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm of the present invention can help an integrating sphere light source achieve high-precision, high-uniformity, and large-dynamic-range radiance output.

[0037] like Figure 1As shown, the present invention comprises a high-precision, wide-dynamic-range, and highly uniform electric aperture, comprising a cover plate 1, a combined aperture blade 2, a high-precision slide rail 3, a base 4, a motor pressure block 5, a high-precision motor 6, a TEC cooling block 7, and heat sink fins 8. It should be understood that the high-precision motor 6 can be a stepper motor or other motor operating in a linear motion manner. It should also be understood that the light outlet shape of the combined aperture blade 2 and the base 4 can be any desired axially symmetrical shape and is not limited to a diamond shape. The cover plate 1 is fixed to the upper position of the base 4 by screws. The high-precision slide rail 3 is first fitted into the finely machined groove mounting surface of the base 4 and then screwed in through the left and right through-holes of the base 4. A metal gasket is placed under the combined aperture blade 2 and gently pressed against the upper surface of the base. After adjusting the position appropriately, the combined aperture blade is fixed to the high-precision slide rail with screws, and the metal gasket is finally removed. Place the high-precision motor 6 in the fixed groove of the base 4, then install the motor pressure block 5 on the fixed groove, pressing the head of the high-precision motor 6 tightly. Finally, connect the fixed head of the combined aperture plate 2 to the push rod portion of the high-precision motor 6. Squeeze an appropriate amount of silicone adhesive into the gap between the high-precision motor 6 and the fixed boss of the base 4 to achieve a soft connection between the base 4 and the high-precision motor 6. Apply an appropriate amount of silicone adhesive to other screw fixing areas to prevent the screws from loosening due to impact or vibration. The TEC cooling block 7 is bonded to the base 4 below the high-precision motor 6 with thermally conductive silicone adhesive, and the heat sink fins 8 are also fixed below it with thermally conductive silicone adhesive. The internal cavity of the aperture needs to be sprayed with matte paint or oxidized black to increase the surface light absorption rate.

[0038] like Figure 2 As shown in the schematic diagram of the fully open state of the aperture system perpendicular to the direction of movement of the high-precision motor, the large-angle diffuse light emitted from the light outlet of the integrating sphere input light source enters the aperture system through the cover plate 1. Considering that the diffuse light will be reflected when blocked to produce stray light, affecting the surface uniformity of the output light, the diameter D1 of the light entrance hole of the cover plate 1 needs to be greater than or equal to the diameter D2 of the light exit hole of the integrating sphere input light source. Because the energy of the scattered light of the integrating sphere is mainly concentrated in the angle range of ±60°, the design size of D1 needs to meet the requirement of not blocking the light entering the integrating sphere within ±60°. The light outlet of the integrating sphere should be as close as possible to the light entrance hole of the cover plate 1, and the thickness of the light entrance hole of the cover plate 1 should not be too thick, otherwise it will affect the surface uniformity level of the irradiance output.

[0039] After light enters the aperture system, portion a enters the aperture aperture of the combined aperture sheet, portion b illuminates the surface of the combined aperture sheet, and portion c illuminates other parts of the aperture system's internal cavity. The light entering portion a is the effective output light required by the aperture system. After undergoing multi-level constraint through the four aperture apertures of the combined aperture sheet 2 and the aperture aperture aperture of the base 4, it ultimately forms the aperture's output light. The interior of the combined aperture sheet 2 constrains light, and diffuse light with large angles is gradually absorbed by the cavity within the combined aperture sheet 2. The spacing of the aperture sheets in this scheme decreases as they approach the light exit aperture, consistent with the distribution characteristics of diffuse light output from an integrating sphere.

[0040] In addition to being partially absorbed, part b of the light is also reflected onto the internal cavity surface of the aperture system, forming stray light within the aperture system together with part c. In order to increase the light absorption capacity of the combined aperture plate 2 and the cavity interior, the height H from the surface of the combined aperture plate 2 to the cavity surface should be at least 0.3 times D2 in the design, and the width D3 of the combined aperture plate 2 should be sufficient to allow the combined aperture plate 2 to receive light output within ±60° of the integrating sphere aperture.

[0041] like Figure 3 The schematic diagram of the diaphragm system in the closed state parallel to the diaphragm movement direction shows that when the aperture of the combined diaphragm blade 2 and the light exit hole of the base 4 do not overlap, the diaphragm is theoretically in a completely closed state. However, since a small amount of light still leaks out of the light exit hole through multiple reflections when the diaphragm is closed, a small amount of light leakage occurs. For low-light radiation sources, it is required that the radiant flux leaking from the diaphragm in the closed state is very low. Figure 3 As shown, leaked light has two paths: path e, where light at the aperture of the combined aperture plate 2 is reflected into the light exit aperture, and path f, where light reflected within the cavity is reflected multiple times and then enters the light exit aperture. The smaller the distance L1 between the bottom of the combined aperture plate 2 and the base 4, the smaller the space light can enter, meaning less light leaks. The preferred high-precision motor 6 and high-precision slide rail 3 of the present invention can ensure a parallelism of 0.03° and enable smooth movement within a range where L1 is less than 0.2mm. The longer the minimum distance L2 between the aperture hole at the bottom of the combined aperture plate 2 and the light exit aperture, the longer the light transmission path, the more times the light is reflected, and the less light leaks. Therefore, within the operating range of the high-precision motor 6, increasing the length of L2 can reduce light leakage. Designing a multi-level matte groove structure near the light exit aperture and spraying it with light-absorbing paint or performing an oxidized blackening treatment increases the absorption area, making it easier to capture leaked light. Through the above design, the leaked light can be reduced to only 0.0001% of the radiant flux level when the aperture is fully opened.

[0042] The high-precision motor 6 in the present invention is preferably a miniature brushless servo electric linear actuator, which integrates a micro motor, a reducer, a screw mechanism, and a high-precision absolute position sensor. It has the advantages of not losing position information after power failure, not requiring a zero return operation, and a drive control system, and can achieve high-precision servo control within the travel range.

[0043] like Figure 4 As shown, the combined aperture plate 2 is composed of a first-level aperture plate 21, a second-level aperture plate 22, a third-level aperture plate 23, and an aperture plate seat 24. It should be understood that the aperture plate can be one or more plates according to needs. All parts of the combined aperture plate 2 are sprayed with matte paint or oxidized blackening treatment is adopted to increase the surface light absorption rate. By adopting a multi-level absorption scheme of the aperture plate, the roughness of the aperture plate surface can be increased or measures such as knurling and scoring can be adopted to increase the surface area of ​​the aperture plate, and more matte paint and blackening substances can be attached. On the other hand, the preferred scheme of this scheme is a rhombus. The rhombus shape is symmetrical about the diagonal and the 45° direction of the diagonal, which is conducive to the uniform distribution of the irradiance of the light output, that is, it ensures the high surface uniformity of the irradiance output level. The multi-level aperture plate structure multiplies the absorption area of ​​the combined aperture plate 2 for light, and through the multi-level absorption of the divergent stray light, it ensures the high uniformity level of the final irradiance output. This indicator is crucial for the uniformity indicator of high-uniform micro-light radiation light sources.

[0044] like Figure 5 As shown, the base 4 has four main structures: a fixing groove 41, a flexible connection boss 42, a slide rail fixing groove 43, and a light exit hole 44. The fixing groove 41 is designed to correspond to the shape of the head of the high-precision motor 6. The motor pressure block 5 presses the high-precision motor 6 into the fixing groove 41. The flexible connection boss 42 does not directly contact the sides of the high-precision motor 6, leaving a certain gap. In this invention, the gap width is preferably 0.2 mm. By injecting an appropriate amount of silicone adhesive into the gap, the silicone does not need to completely fill the gap; as long as the gap is half-filled, the flexible connection between the main body of the high-precision motor 6 and the base 4 is completed. Testing has shown that the flexible connection can effectively prevent certain impact and vibration conditions and meet the high vibration and impact requirements. The slide rail fixing groove 43 is a precision-machined groove mounting surface for the high-precision slide rail 3. During machining, a certain degree of parallelism must be achieved to ensure that the combined aperture blade 2 does not interfere or rub against the upper surface of the base 4 during precise linear motion, thus ensuring the accuracy of linear motion. The light exit hole 44 is the aperture stop of the aperture system, which limits the maximum value of the radiant flux emitted by the stop. The size of the light exit hole 44 is designed according to the stroke resolution of the high-precision motor 6 and the size of the integrating sphere entrance.

[0045] A multi-level matte structure is designed near the light exit hole 44 of the base 4, and a multi-level groove structure is designed near the light exit hole of the base 4. The roughness level of the groove structure can be increased or black velvet strips can be pasted to increase its light absorption surface area. The depth of the groove can maintain a certain regular distribution. The present invention preferably has a groove depth that is deeper the closer to the light exit hole, and the preferred depth range is within 0.05mm to 0.3mm. The shape of the groove can be a variety of shapes, which can be square, trapezoidal, triangular, semicircular, etc. The present invention is preferably rectangular, and the spacing between the grooves is distributed according to a certain regularity. The preferred distribution regularity of the present invention is that the closer to the light exit hole, the smaller the spacing. In addition, the surface of the groove can be sprayed with matte paint or blackened. If a black velvet strip is added to the groove, the material with better light absorption should be selected. And the black velvet strip is coated with an appropriate amount of lubricating oil to ensure that there is no friction and interference between the combined aperture piece.

[0046] like Figure 6 As shown, the aperture system uses a high-precision motor 6 to move the combined aperture blade 2 back and forth, creating a certain overlap area with the light exit aperture, thereby adjusting the system's output radiant flux. The diamond diagonal length of the aperture blade seat 24 of the combined aperture blade 2 is Q1, the diamond diagonal length of the light exit aperture is Q2, and the motor displacement is X. The aperture adjustment coefficient is as follows:

[0047] T(x min )=x min 2 / Q 2

[0048] Theoretically, the minimum step size X of the motor used for the aperture is min The smaller the value, the lower the adjustment coefficient of the aperture, and the stronger the adjustment ability of the aperture system for light. The total number of steps of the preferred high-precision motor 6 of the present invention is 16384, the minimum number of steps per time is 2, and the stroke Q is 30mm. min =3.67μm. The diagonal of the aperture diamond of the present invention is preferably designed to be 15mm. Substituting it into the formula, the adjustment coefficient of the aperture is calculated to be 5.99e -8 , which can meet the radiance adjustment requirements within a range of seven orders of magnitude. Preferably, the repeatability of the high-precision motor 6 is at the level of ±10 μm, which can ensure that the output of the radiant flux can be maintained at a high repeatability level.

[0049] Calibration experiments require multiple high-precision motor push rods to move the combined aperture blades to adjust the aperture system's radiant flux output. High repeatability ensures accuracy. In most cases, the dynamic range of the aperture system's output is primarily determined by the minimum light leakage and its adjustability. By combining the aperture system's repeatability, light leakage, adjustability, and surface uniformity, the present invention achieves adjustable radiant flux over a six-order-of-magnitude range, enabling low-light source sources to achieve precise radiant brightness output or highly uniform irradiance output within this six-order-of-magnitude range.

[0050] The present invention can be installed at the light exit aperture of an integrating sphere light source or other uniform light source, providing the light source system with highly repeatable, wide dynamic range radiance or highly uniform irradiance output. The examples described above are merely specific embodiments of the present invention; any modifications and substitutions made by those skilled in the art within the technical solution of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A high-precision, wide-dynamic-range, and high-uniformity electric diaphragm, characterized by: It includes a cover plate, a combined aperture plate, a high-precision slide rail, a base, a motor pressing block, a high-precision motor, a TEC cooling block and a heat dissipation fin; the cover plate is connected to the integrating sphere for light input, and the base is connected to the integrating sphere for light input; The cover and base are connected by screws to form the main part of the electric aperture. The head of the high-precision motor is fixed in the fixing groove of the base and fixed by the motor pressure plate. The high-precision slide rail is first installed on the precision-machined groove mounting surface of the base, adjusted in position, and then fixed to the base with screws. The combined aperture piece is padded with a metal gasket, fixed to the high-precision slide rail, and finally connected to the push rod of the high-precision motor by screws, so that the combined aperture piece can make precise movements parallel to the base. The high-precision motor is softly connected to the four bosses on the base by silicone adhesive. The push rod of the high-precision motor makes linear motion, controlling the linear motion of the combined aperture piece. The intersection area between the light-shielding hole on the combined aperture piece and the light-emitting hole on the base is changed through linear motion, thereby changing the radiant flux value output by the aperture system. The TEC cooling block is fixed to the bottom of the high-precision motor using thermally conductive silicone adhesive, and the other side is connected to the heat sink. The temperature of the high-precision motor is monitored using the high-precision motor's own temperature sensor. The TEC cooling block is used to increase or decrease the temperature around the high-precision motor to achieve temperature control of the high-precision motor. The linear motor and high-precision slide rail ensure that the combined aperture piece makes precise linear reciprocating motion in the diagonal direction of the diamond aperture hole, and maintains an angle of 0.03° and a distance of 0.02mm with the upper surface of the base, ensuring the repeatability of the radiation flux output of the aperture system. The light inlet of the cover is designed to be larger than the opening of the input integrating sphere. The ratio of the two is determined by the distance between the light inlet and the opening of the integrating sphere. The farther the integrating sphere entrance is from the light inlet, the larger the aperture of the light inlet should be. The opening of the integrating sphere is as close to the light inlet as possible.

2. The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to claim 1, characterized in that: The aperture thickness of the light inlet of the aperture in the combined aperture sheet is as small as possible, and there is no structure near the aperture that reflects the incident light from the light inlet. The combined aperture sheet is composed of a plurality of aperture sheets stacked up and down, and the spacing between the individual apertures is distributed according to a certain pattern. The surface is sprayed with a matte paint with a high extinction ratio or subjected to a blackening treatment to enhance the surface light absorption rate.

3. The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to claim 1, characterized in that: The shapes of the light entrance hole of the cover plate, the light shielding hole of the stray light eliminating aperture piece, and the light exit hole of the base are symmetrical with respect to the linear motion direction of the high-precision motor, and include circular, polygonal or exponential shapes; the size of the aperture hole of the combined aperture piece and the aperture seat gradually decreases from top to bottom, and the final light exit hole of the base is an aperture aperture, which limits the maximum value of the output radiation.

4. The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to claim 1, characterized in that: The combined aperture piece has no bosses or reflective surfaces within the direction range of ±60° from the normal line of the integrating sphere port; the combined aperture piece is processed with multi-level grooves on the side facing the light entrance hole, and is sprayed with matte paint or subjected to surface oxidation blackening treatment.

5. The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to claim 1, characterized in that: There is a fixing groove on the base for the high-precision motor head. The fixing groove does not directly contact the motor head, leaving a gap; the gap is filled with silicone adhesive; the base also has four bosses on the left and right sides of the high-precision motor, and gaps are also left. Soft connection is achieved by injecting silicone adhesive into the gaps.

6. The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to claim 1, characterized in that: The base has two through holes on each side and a precision-machined groove mounting surface with a shape slightly larger than the slide rail and a certain parallelism tolerance requirement processed on the base under the high-precision slide rail. The two are used to fix the high-precision slide rail; the high-precision slide rail is first installed on the combined aperture piece and then installed on the base; the groove plane limits the installation angle of the high-precision slide rail and the movement direction of the high-precision motor push rod to a very low level, and the distance between the bottom of the combined aperture piece and the base is kept at a very small distance, so that the combined aperture piece moves parallel to the light exit hole plane of the base.

7. The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to claim 1, characterized in that: The TEC cooling block is installed at the bottom of the base directly below the high-precision motor. It consists of TEC and heat dissipation fins, which accurately controls the temperature to ±0.1 degrees of the appropriate operating temperature, ensuring the normal accuracy level of the high-precision motor.

8. The high-precision, wide-dynamic-range, and high-uniformity electric diaphragm according to claim 1, characterized in that: Several light-absorbing grooves with similar shapes to the light outlet are set near the light outlet of the base and are compactly arranged near the light outlet of the base in a certain regular form; the inside of the light-absorbing grooves is sprayed with matte paint or blackened to increase the surface light absorption rate.

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