Laser beam divergence angle measuring device with thermocouple
By installing a thermocouple on the back side of the aperture stop and combining a laser power meter, the laser beam divergence angle is directly measured, which solves the problems of low measurement accuracy, large energy loss and easy device damage in the prior art, and achieves high-precision, stability and fast feedback laser beam divergence angle measurement.
Patent Information
- Application Number
- CN202421773209.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2025-08-08
- Estimated Expiration
- 2034-07-25
AI Technical Summary
The prior art has problems such as low accuracy, large energy loss, complex calculations and easy device damage when measuring the divergence angle of the laser beam, especially when measuring ultra-high power lasers.
The aperture stop design with a thermocouple is adopted. By installing a thermocouple on the back of the aperture stop and combining a laser power meter, the divergence angle of the laser beam is directly measured to avoid spectroscopy or attenuation. The divergence angle is calculated by using the aperture stop movement to protect the aperture from damage.
High-precision measurement of laser beam divergence angle is achieved, which reduces energy loss, simplifies the calculation process, and improves the durability of the device, ensuring the smooth progress of measurement.
Smart Images
Figure CN223205010U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a laser beam divergence angle measuring device with a thermocouple. Background Art
[0002] Laser technology has become an integral part of modern science and technology, finding widespread application in industrial manufacturing, medical equipment, communications, and other fields. The divergence angle of a laser beam is a crucial parameter, determining its propagation characteristics and energy distribution, and is crucial for the design and use of lasers. Therefore, accurately measuring the divergence angle of a laser beam is crucial. Beam measurement technology is used to measure beam parameters, typically including intensity, direction, and spatial distribution. Aperture attenuation is a commonly used bridge measurement tool, measuring beam power by limiting the beam diameter. However, traditional aperture attenuation only measures the total power of a beam and cannot accurately measure its divergence angle. Thermocouples are a commonly used temperature measurement tool, converting temperature signals into electrical signals, enabling precise temperature measurement. However, their application in beam measurement is limited, particularly for measuring the divergence angle of laser beams. Existing solutions primarily involve splitting a laser beam into multiple segments through beam splitting or attenuation, measuring the power of each segment separately, and calculating the total power and divergence angle of the laser beam. In addition, there are some solutions that use variable light attenuation to measure the divergence angle of laser beams at different powers by changing the size of light attenuation. However, there are some problems with existing technologies in practical applications. First, the splitting or attenuation method will partially lose laser energy, affecting the accuracy of the measurement results. Secondly, the variable light attenuation may be damaged when subjected to ultra-high power laser measurement, resulting in measurement failure. In addition, the existing solutions usually have complex calculation processes, which are not conducive to real-time measurement and fast input. At present, engineers are in urgent need of solving the following problems: 1. How to directly measure the laser beam without splitting or attenuation to improve the divergence angle and ensure the accuracy of the measurement results;
[0003] 2. How to protect the aperture diaphragm from damage when performing laser measurement under ultra-high power conditions to ensure smooth measurement;
[0004] 3. How to simplify the calculation process and achieve technical issues such as real-time measurement and rapid feedback. Utility Model Content
[0005] The purpose of the utility model is to provide a device that can detect the divergence angle by accurately cooperating with the aperture diaphragm and the power meter, so as to realize real-time measurement and protect the aperture diaphragm from being damaged.
[0006] In order to solve the above problems, the present invention provides a device for measuring the divergence angle of a laser beam with a thermocouple; the device comprises a measuring device frame 1, an aperture diaphragm 3, a laser beam output structure 4, a position adjustment device 5, and a thermocouple 6, wherein the position adjustment device 5 comprises a slide rail and a slider, the slider is slidably arranged on the slide rail, and the slider can slide on the slide rail; the slide rail is installed on the device frame 1; the aperture diaphragm 3 is fixedly installed on the upper side of the slider of the position adjustment device 5 so that the aperture diaphragm can move back and forth along the slide rail, and the straight line trajectory formed by the back and forth movement of the aperture diaphragm is parallel to the optical axis of the laser output by the laser beam output structure; the measuring device frame 1 comprises a frame bottom plate and a frame side plate, the frame bottom plate is connected to the frame side plate, and the frame side plate comprises a front side plate and a rear side plate; an output head mounting portion for mounting the laser beam output structure is provided on the front side plate of the frame, the output head mounting portion fixes the laser beam output structure on the front side plate of the frame, the laser beam output structure passes through the front side plate, and the laser output by the laser beam output structure is emitted from the direction of the front side plate toward the direction of the rear side plate; a thermocouple 6 is installed on the back side of the aperture diaphragm.
[0007] Preferably, a laser power meter 2 is installed on the rear side panel of the measuring device frame. The laser power meter 2 can measure the power of light emitted from the front side panel toward the rear side. The laser output by the laser beam output structure passes through the aperture diaphragm, and the light power of the laser passing through the aperture diaphragm and falling into the photometric area of the laser power meter accounts for at least greater than 95%.
[0008] Preferably, the slide rail is in the form of a linear slide rod; a front fixing portion and a rear fixing portion are respectively provided on the front and rear sides of the slide rail; the front fixing portion of the slide rail is fixed on the front side plate, and the rear fixing portion of the slide rail is fixed on the rear side plate. Correspondingly, both the front side plate and the rear side plate have installation areas for installing the slide rail, so that the slide rail is fixed between the front side plate and the rear side plate, and the slide rail is parallel to the optical axis of the laser output by the laser beam output structure.
[0009] Preferably, when the aperture stop moves back and forth along the slide rail, the central optical axis of the light beam output by the laser beam output structure is always kept passing through the central area of the aperture stop.
[0010] Preferably, the aperture stop adopts a dark aperture stop, and a thermocouple is installed on the attenuated back side of the dark aperture stop.
[0011] Preferably, the aperture stop and the thermocouple are mounted in the path of the laser beam so that the laser aperture stop and the thermocouple are positioned such that the center line of the laser beam coincides with the center lines of the aperture stop and the thermocouple.
[0012] Preferably, the diameter of the aperture is 20 mm-25 mm; the diameter of the aperture aperture is larger than the diameter of the laser beam at the initial position.
[0013] Preferably, the aperture diaphragm is a variable diameter diaphragm, and the diameter of the diaphragm can be selected between 20 mm and 25 mm; the diameter of the aperture diaphragm is larger than the diameter of the laser beam at the initial position.
[0014] Preferably, the aperture is made of tungsten alloy or ceramic, and the thermocouple is a K-type thermocouple or a J-type thermocouple; the measuring device frame further comprises a frame top plate connected to the frame side plates, and the frame side plates further comprise a left plate and / or a right plate.
[0015] Preferably, while keeping the shape of the aperture diaphragm unchanged, the aperture diaphragm is moved so that the relative position of the laser beam on the side wall of the aperture diaphragm changes, allowing the thermocouple to just detect the temperature change. At this time, the diameter of the aperture diaphragm is the diameter d of the laser beam at the aperture diaphragm position, and the distance between the aperture diaphragm and the laser beam output structure is recorded; based on the recorded data, the divergence angle of the laser beam is calculated; the specific calculation formula is as follows: θ = arctan(d / L) where θ is the divergence angle of the laser beam, d is the diameter of the laser beam, and L is the distance between the aperture diaphragm and the laser beam output structure.
[0016] The beneficial effects of the present invention are:
[0017] 1. Directly measure the laser beam without splitting or attenuation to improve the divergence angle and thus the accuracy of the measurement result; Accurate measurement: The present invention installs a thermocouple on the back side of the attenuated aperture to accurately match the attenuated laser beam with the power meter for detection, and can directly measure the laser divergence angle without splitting or attenuation, thereby improving the measurement accuracy.
[0018] Energy loss: The present invention calculates the laser divergence angle by avoiding the light attenuation movement angle, thus avoiding the disadvantage of variable light attenuation that cannot withstand high-voltage power laser measurement, thereby avoiding the problem of laser energy loss due to splitting or attenuation.
[0019] Simplified calculation process: The present invention reduces the complicated calculation process and can calculate the divergence angle of the laser beam by simply obtaining the moving distance of the aperture stop, thereby simplifying the calculation process and facilitating real-time measurement and rapid feedback.
[0020] Improved durability: The present invention uses a sensitive thermocouple to sense temperature, avoiding the possibility of aperture burnout when subjected to ultra-high power laser measurements. This improves measurement stability and reliability.
[0021] 2. When performing laser measurements under ultra-high power conditions, the aperture diaphragm must be protected from damage to ensure smooth measurement. The aperture diaphragm is used to limit the diameter of the laser beam, and the size of the aperture diaphragm can be changed to accommodate laser beams with different fiber cores. The diameter of the laser beam can be adjusted to control the divergence angle of the laser beam. This method can directly measure the divergence angle of the laser beam without the need for splitting or attenuation, thereby improving the accuracy of the measurement results.
[0022] A thermocouple mounted on the back of the clear aperture diaphragm accurately detects the laser beam attenuation position in conjunction with a power meter. This design also allows the aperture diaphragm to precisely measure the divergence angle in conjunction with the power meter. This design protects the aperture diaphragm from damage when measuring ultra-high-power lasers, ensuring smooth measurement. This solves technical issues such as real-time measurement and rapid feedback, improving measurement accuracy and durability. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is a schematic diagram of the external structure of the utility model.
[0024] Figure 2 It is a schematic diagram of the internal structure of the utility model.
[0025] Figure 3 It is a diagram of the installation position of the thermocouple of the present invention. DETAILED DESCRIPTION
[0026] The technical solution of the present invention will be further described below with reference to the accompanying drawings and through specific implementation methods.
[0027] like Figure 1 As shown, the present invention relates to a device for measuring the divergence angle of a laser beam with a thermocouple, comprising a measuring device frame 1, an aperture stop 3, a laser beam output structure 4, a position adjustment device 5, a thermocouple 6, and preferably, a laser power meter 2. The position adjustment device 5 comprises a slide rail and a slider, the slider being slidably mounted on the slide rail and capable of sliding on the slide rail. The aperture stop 3 can be fixedly mounted on the upper side of the slider of the position adjustment device 5. The slide rail is mounted on the device frame 1. The slide rail is a linear slide rail.
[0028] The measuring device frame 1 includes a frame bottom plate and frame side plates, the frame bottom plate being connected to the frame side plates. Preferably, the measuring device frame 1 also includes a frame top plate connected to the frame side plates. The frame side plates include at least a front side plate and a rear side plate, and preferably may also include a left side plate and / or a right side plate. A laser power meter 2 is mounted on the rear side plate of the frame. The laser power meter 2 can measure the power of light emitted from the front side plate toward the rear side. An output head mounting portion for mounting a laser beam output structure is provided on the front side plate of the frame. The output head mounting portion fixes the laser beam output structure to the front side plate of the frame. The laser beam output structure passes through the front side plate, and the laser output from the laser beam output structure is emitted from the front side plate toward the rear side plate. Generally speaking, the laser beam that is not blocked by the aperture diaphragm should basically fall into the photometric area of the laser power meter (the laser output by the laser beam output structure passes through the aperture diaphragm, and the power of the laser passing through the aperture diaphragm that falls into the photometric area of the laser power meter accounts for at least greater than 95%). Preferably, the central optical axis of the light beam output by the laser beam output structure should preferably pass through the center of the photometric area of the laser power meter.
[0029] The position adjustment device includes a slide rail, and the slide rail can be in the form of a commonly used flat linear rail or a linear slide rod. Preferably, the slide rail is in the form of a linear slide rod. A front fixing portion and a rear fixing portion are respectively provided on the front and rear sides of the slide rail. The front fixing portion of the slide rail is fixed on the front side plate, and the rear fixing portion of the slide rail is fixed on the rear side plate (correspondingly, both the front side plate and the rear side plate have installation areas for installing the slide rail), so that the slide rail is fixed between the front side plate and the rear side plate. The slide rail should be required to be linear, and the slide rail should be parallel to the optical axis of the laser output by the laser beam output structure. Of course, under different slide rail forms, such as when a flat groove type slide rail is used, the slide rail can also be directly installed on the frame bottom plate for fixation.
[0030] The position adjustment device also includes a slider, which is slidably mounted on a slide rail and can slide on the slide rail. The aperture stop 3 can be fixedly mounted on the upper side of the slider of the position adjustment device 5, so that the aperture stop can move back and forth along the slide rail. The straight line formed by the back and forth movement of the aperture stop is parallel to the optical axis of the laser light output by the laser beam output structure. In the initial position, the central optical axis of the light beam output by the laser beam output structure passes through the central region of the aperture stop. It is foreseeable that in the initial position, the diameter of the aperture stop needs to be larger than the diameter of the laser beam at the initial position. At the same time, it is required that when the aperture stop moves back and forth along the slide rail, the central optical axis of the light beam output by the laser beam output structure always passes through the central region of the aperture stop.
[0031] The aperture diaphragm has a front side and a back side. Preferably, the aperture diaphragm is a dark diaphragm, and a thermocouple is installed on the back side of the dark aperture diaphragm to reduce the intensity. The diameter of the diaphragm is preferably 20 mm to 25 mm. Preferably, the aperture diaphragm can be a variable diameter diaphragm, and the diameter of the diaphragm can be selected between 20 mm and 25 mm to accommodate laser beams of different fiber cores.
[0032] Specific measurement process: Step 1: Prepare an aperture diaphragm 3. The diameter of this diaphragm can be selected between 20mm and 25mm to accommodate laser beams of different fiber cores. The diaphragm should be made of a high-temperature and high-pressure resistant material, such as tungsten alloy or ceramic, to ensure the stability and reliability of the equipment when measuring ultra-high-power lasers.
[0033] Step 2: Install thermocouple 6 on the back of the dark aperture stop. The selection of thermocouple should be based on the output power of the laser and the measurement accuracy requirements. Choose a thermocouple with high resistance, good stability and fast response speed, such as K-type thermocouple or J-type thermocouple.
[0034] Step 3: Install the aperture stop and thermocouple in the path of the laser beam so that the center line of the laser beam coincides with the center line of the aperture stop and thermocouple.
[0035] Step 4: Use the position adjustment device 5 to adjust the position of the aperture stop so that the diameter of the laser beam output by the laser beam output structure 4 reaches the desired size at the aperture stop. During this process, the reading of the laser power meter 2 can be observed to determine whether the laser beam power reaches the desired level (because the divergence angle may vary at different powers, this method can provide more standardized and reliable divergence angle data).
[0036] Step 5: While maintaining the shape of the aperture diaphragm (and, naturally, its diameter), move the aperture diaphragm so that the relative position of the laser beam to the aperture diaphragm wall changes, allowing the thermocouple to detect the temperature change. The aperture diaphragm diameter is then the laser beam diameter (combined with the power meter's measurement, this allows for a more precise determination of the laser beam diameter). During this process, record the distance the aperture diaphragm moves from its initial position to its final position (i.e., the distance between the aperture diaphragm and the laser beam output structure) and the reading of the laser power meter assembly.
[0037] Step 6: Calculate the laser beam divergence angle based on the recorded data. The specific calculation formula is as follows: θ = arctan(d / L), where θ is the laser beam divergence angle, d is the laser beam diameter, and L is the distance of the aperture stop (i.e., the distance between the aperture stop and the laser beam output structure). Through the above steps, the laser beam divergence angle can be accurately measured without splitting or attenuating the light, thereby improving the accuracy of the measurement results. Furthermore, by installing a thermocouple on the back side of the aperture stop, the aperture stop can be protected from damage, ensuring smooth measurement. The laser beam diameter d now corresponds to the aperture stop diameter.
[0038] The laser divergence angle is calculated by moving the aperture stop. This method simplifies the calculation process, enabling real-time measurement and rapid feedback. The simplified calculation process allows the laser beam divergence angle to be calculated simply by determining the distance the aperture stop is moved.
[0039] By changing the position of the aperture diaphragm, different laser beam diameters can be obtained at different positions. Then, by measuring the corresponding laser power with a power meter, the laser beam divergence angle can be calculated. Using an effective laser power meter component, the laser beam passing through the aperture diaphragm can be accurately measured on the laser power meter, thereby improving the measurement accuracy of the laser divergence angle.
[0040] The aperture diaphragm and thermocouple are made of high-temperature and high-pressure resistant materials to ensure the stability and reliability of the equipment when subjected to ultra-high power laser measurements.
[0041] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are intended solely to illustrate the principles of the present invention and should not be construed in any way as limiting the scope of protection of the present invention. Based on the explanations herein, those skilled in the art will be able to devise other specific implementations of the present invention without inventive effort, and such implementations will fall within the scope of protection of the present invention.
Claims
1. A device for measuring the divergence angle of a laser beam with a thermocouple, comprising a measuring device frame, an aperture stop, a laser beam output structure, a position adjustment device, and a thermocouple, characterized in that: The position adjustment device includes a slide rail and a slider, the slider is slidably set on the slide rail, and the slider can slide on the slide rail; the slide rail is installed on the device frame; the aperture diaphragm is fixedly installed on the upper side of the slider of the position adjustment device so that the aperture diaphragm can move back and forth along the slide rail, and the straight trajectory formed by the back and forth movement of the aperture diaphragm is parallel to the optical axis of the laser output by the laser beam output structure; the measuring device frame includes a frame bottom plate and a frame side plate, the frame bottom plate is connected to the frame side plate, and the frame side plate includes a front side plate and a rear side plate; an output head mounting part for mounting the laser beam output structure is provided on the front side plate of the frame, the output head mounting part fixes the laser beam output structure on the front side plate of the frame, the laser beam output structure passes through the front side plate, and the laser output by the laser beam output structure is emitted from the front side plate toward the rear side plate; a thermocouple is installed on the back side of the aperture diaphragm.
2. The laser beam divergence angle measuring device with a thermocouple according to claim 1, characterized in that: A laser power meter is installed on the rear panel of the measuring device frame. The laser power meter can measure the power of light emitted from the front panel toward the rear side. The laser output by the laser beam output structure passes through the aperture diaphragm, and the light power of the laser passing through the aperture diaphragm and falling into the photometric area of the laser power meter accounts for at least greater than 95%.
3. The laser beam divergence angle measuring device with a thermocouple according to claim 2, characterized in that: The slide rail is in the form of a linear slide rod; a front fixing portion and a rear fixing portion are respectively provided on the front and rear sides of the slide rail; the front fixing portion of the slide rail is fixed on the front side plate, and the rear fixing portion of the slide rail is fixed on the rear side plate. Correspondingly, both the front side plate and the rear side plate have installation areas for installing the slide rail, so that the slide rail is fixed between the front side plate and the rear side plate, and the slide rail is parallel to the optical axis of the laser output by the laser beam output structure.
4. The laser beam divergence angle measuring device with a thermocouple according to claim 2, characterized in that: When the aperture stop moves forward and backward along the slide rail, the central optical axis of the light beam output by the laser beam output structure is always kept passing through the central area of the aperture stop.
5. The laser beam divergence angle measuring device with a thermocouple according to claim 2, characterized in that: The aperture diaphragm adopts a dark diaphragm, and a thermocouple is installed on the back side of the dark aperture diaphragm.
6. The device for measuring the divergence angle of a laser beam with a thermocouple according to claim 5, characterized in that: The aperture stop and the thermocouple are mounted in the path of the laser beam so that the laser aperture stop and the thermocouple are positioned so that the center line of the laser beam coincides with the center lines of the aperture stop and the thermocouple.
7. The laser beam divergence angle measuring device with a thermocouple according to claim 2, characterized in that: The diameter of the aperture is 20 mm to 25 mm; the diameter of the aperture aperture is larger than the diameter of the laser beam at the initial position.
8. The laser beam divergence angle measuring device with a thermocouple according to claim 2, characterized in that: The aperture diaphragm selects a variable diameter diaphragm, and the diameter of the diaphragm can be selected between 20 mm and 25 mm; the diameter of the aperture diaphragm is larger than the diameter of the laser beam at the initial position.
9. The laser beam divergence angle measuring device with a thermocouple according to claim 2, characterized in that: The aperture is made of tungsten alloy or ceramic, and the thermocouple is a K-type thermocouple or a J-type thermocouple; the measuring device frame further comprises a frame top plate connected to the frame side plates, and the frame side plates further comprise a left plate and / or a right plate.
10. The laser beam divergence angle measuring device with a thermocouple according to claim 2, characterized in that: While keeping the aperture diaphragm shape unchanged, the aperture diaphragm is moved to change the relative position of the laser beam to the side wall of the aperture diaphragm, allowing the thermocouple to just detect the temperature change. At this time, the diameter of the aperture diaphragm is the diameter d of the laser beam at the aperture diaphragm position. The distance between the aperture diaphragm and the laser beam output structure is recorded. Based on the recorded data, the divergence angle of the laser beam is calculated. The specific calculation formula is as follows: θ = arctan(d / L) where, θ is the divergence angle of the laser beam, d is the diameter of the laser beam, and L is the distance between the aperture stop and the laser beam output structure.