A liquid refractive index measuring device
By using a micrometer and a controllable optical path length device, combined with a laser light source and a mobile phone optical sensor, rapid and accurate measurement of liquid refractive index was achieved, solving the problem of limited measurement range of existing devices and improving measurement accuracy and flexibility.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HENAN NORMAL UNIV
- Filing Date
- 2025-05-09
- Publication Date
- 2026-06-26
AI Technical Summary
Existing liquid refractive index measuring devices have limited measurement ranges and cannot easily convert the refractive index of a liquid into glass thickness parameters of different thicknesses, resulting in insufficient measurement accuracy and flexibility.
The system uses a micrometer to read values and combines it with a controllable optical path device. By adjusting the thickness of the compensator, the refractive index of the liquid is converted into the thickness of glass of different thicknesses. The optical path is adjusted using components such as a laser light source, beam expander, double slit plate and light source receiver. Data analysis is performed using a mobile phone light sensor and Phyphox software to achieve rapid and accurate measurement.
It improves the accuracy and flexibility of liquid refractive index measurement, enabling the rapid and accurate conversion of liquid refractive index into glass thickness, simplifying manual counting steps, and ensuring the accuracy of measurement results.
Smart Images
Figure CN224416718U_ABST
Abstract
Description
Technical Field
[0001] This utility model specifically relates to a liquid refractive index measuring device, belonging to the technical field of measuring devices. Background Technology
[0002] Liquid refractive index measuring devices are mainly used to measure the refractive index of liquids, which is the ratio of the speed of light in a liquid to the speed of light in a vacuum. Refractive index is an important optical parameter that can help identify the type of liquid, as different liquids have different refractive indices. In industrial production, it is used to ensure the purity and consistency of liquid composition. In physics and chemistry experiments, it is used to understand the optical properties of liquids.
[0003] Existing liquid refractive index measuring devices have limited measurement ranges, only measuring refractive index within a specific range. They are not convenient for converting the refractive index of liquids into glass of different thicknesses, nor are they convenient for visualizing the refractive index of liquids into the thickness parameter of glass. Therefore, we propose a liquid refractive index measuring device. Utility Model Content
[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a liquid refractive index measuring device to improve measurement accuracy and flexibility.
[0005] A liquid refractive index measuring device includes a base plate. A slide rail is symmetrically arranged on the top of the base plate. Four sliding bases are arranged in an array from left to right on the top of the slide rails. A bracket is fixedly installed on the top of each sliding base. A positioning mechanism for positioning the sliding base is provided on each sliding base. A laser source, a beam expander, a double-slit plate, an adjustable single slit, and a light source receiver are sequentially fixedly connected to the four sliding bases from left to right via the bracket. The laser source, beam expander, double-slit plate, adjustable single slit, and light source receiver are aligned in a straight line. Two light slits are provided on the double-slit plate. A cuvette and a first wedge glass are fixedly connected to the side of the double-slit plate, and the cuvette and the first wedge glass are arranged parallel to each other on one side of the corresponding light slit. A second wedge glass is provided on the side of the first wedge glass, with the inclined surfaces of the first and second wedge glasses abutting each other. An adjustment component for adjusting the position of the second wedge glass is provided on the double-slit plate.
[0006] Furthermore, the bottom of the sliding base is symmetrically provided with sliding grooves corresponding to the slide rail, and the sliding grooves engage with the slide rail.
[0007] Furthermore, the positioning mechanism includes a threaded ring and a positioning bolt, the threaded ring being fixedly mounted on the sliding base, and the positioning bolt being threadedly connected inside the threaded ring.
[0008] Furthermore, the adjustment assembly includes a frame, a lateral adjustment mechanism, and a longitudinal adjustment mechanism. The frame is fixedly installed on the side of the double-seam plate, and the lateral adjustment mechanism and the longitudinal adjustment mechanism are disposed inside the frame.
[0009] Furthermore, the lateral adjustment mechanism includes a first micrometer screw gauge, a knob, and a slider. The first micrometer screw gauge is disposed inside the frame, the side of the knob is fixedly connected to one end of the first micrometer screw gauge, and the slider is slidably disposed inside the frame, with one end of the first micrometer screw gauge fixedly connected to the slider.
[0010] Furthermore, the longitudinal adjustment mechanism includes a support block, a fixed ring, a second micrometer screw gauge, and a connecting block. One end of the support block is fixedly connected to the slider. The fixed ring is embedded inside the support block. The second micrometer screw gauge is connected inside the fixed ring. The connecting block is fixedly installed at the bottom of the second wedge-shaped glass. One end of the second micrometer screw gauge is connected to a movable frame. A guide rod is fixedly installed inside the movable frame and passes through the connecting block. A pressure spring is arranged around the guide rod. One end of the pressure spring is fixedly connected to the inner wall of the movable frame, and the other end of the pressure spring is fixedly connected to the connecting block.
[0011] Beneficial effects:
[0012] This invention uses a micrometer spiral to read values, replacing the traditional guide rail reading. It also features a self-made controllable optical path device. By adjusting the thickness of a compensator-like device, the refractive index of the liquid is converted into glass of different thicknesses. The parameters are then converted into a more visual representation of the refractive index based on the glass thickness. Different glass thicknesses correspond to different refractive indices. When measuring the refractive index of a liquid using this invention, the corresponding glass thickness can be directly used to find the corresponding refractive index, allowing for rapid results. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0014] Figure 2 This is a schematic diagram of the frame structure of this utility model;
[0015] Figure 3 This is a schematic diagram of the No. 1 and No. 2 wedge glass structures of this utility model;
[0016] Figure 4 This is a schematic diagram of the double-slit plate structure of this utility model;
[0017] Figure 5 This is a schematic diagram of the side structure of the No. 1 wedge-shaped glass and the No. 2 wedge-shaped glass of this utility model;
[0018] Figure 6 This is a schematic diagram of the cuvette structure of this utility model;
[0019] Figure 7 This is a schematic diagram of the illuminance of the point light source of this utility model.
[0020] In the diagram: 1. Base plate; 2. Slide rail; 3. Sliding base; 4. Slide groove; 5. Threaded ring; 6. Positioning bolt; 7. Bracket; 8. Laser light source; 9. Beam expander; 10. Adjustable single slit; 12. Double slit plate; 13. Slit; 14. Cuvette; 15. Frame; 16. No. 1 wedge glass; 17. No. 2 wedge glass; 18. No. 1 micrometer; 19. Knob; 20. Slider; 21. Support block; 22. Fixing ring; 23. No. 2 micrometer; 24. Movable frame; 25. Light source receiver; 26. Guide rod; 27. Connecting block; 28. Compression spring. Detailed Implementation
[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0022] Please see Figure 1-7As shown, a liquid refractive index measuring device includes a base plate 1. A slide rail 2 is symmetrically arranged on the top of the base plate 1. Four sliding bases 3 are arranged in an array from left to right on the top of the slide rail 2. A bracket 7 is fixedly installed on the top of each sliding base 3. A positioning mechanism for positioning the sliding base 3 is provided on each sliding base 3. A laser source 8, a beam expander 9, an adjustable single slit 10, a double slit plate 12, and a light source receiver 25 are sequentially fixedly connected to the four sliding bases 3 from left to right via the bracket 7. The laser source 8, beam expander 9, adjustable single slit 10, double slit plate 12, and light source receiver 25 are aligned in a straight line. Two light slits 13 are provided on the double slit plate 12. A cuvette 14 and a first wedge-shaped glass 16 are fixedly connected to the side of the double slit plate 12. The cuvette 14 and the first wedge-shaped glass 16 are... Glass 16 is arranged parallel to one side of the corresponding light slit 13. A second wedge glass 17 is arranged on the side of the first wedge glass 16, and the inclined surfaces of the first wedge glass 16 and the second wedge glass 17 abut against each other. An adjustment component for adjusting the position of the second wedge glass 17 is provided on the double slit plate 12. When measuring the refractive index of a liquid using a liquid refractive index measuring device, the distance between the laser source 8, beam expander 9, adjustable single slit 10, double slit plate 12, and light source receiver 25 can be adjusted to a predetermined position by adjusting the position of the sliding base 3. The position of the sliding base 3 can be positioned by the positioning mechanism, thereby positioning the laser source 8, beam expander 9, adjustable single slit 10, double slit plate 12, and light source receiver 25. The system emits a laser beam, which is expanded by beam expander 9, directing the light source towards adjustable single slit 10. After passing through adjustable single slit 10, the light source becomes rectangular, directing it towards light slit 13. After passing through light slit 13, the light source is collected by light source receiver 25. As the light source passes through light slit 13, it first passes through cuvette 14, wedge-shaped glass 16, and wedge-shaped glass 17 positioned on one side. Wedge-shaped glass 16 and wedge-shaped glass 17 form a compensator-like structure. When an empty cuvette 14 and the compensator-like structure are placed in front of the double slits, the central bright fringe shifts. The position of wedge-shaped glass 17 can be adjusted by adjusting the components, causing it to slide against the inclined surface of wedge-shaped glass 16, thus changing its thickness and altering the optical path. The liquid to be tested is added into the empty cuvette 14. Both the compensator and cuvette 14 are positioned close to the light-incoming side of the two light slits 13, parallel to them. Finally, the light source, after passing through the compensator and cuvette 14, is received by the light source receiver 25. When the compensator is adjusted to match the refractive index of the liquid in cuvette 14, the light source brightness on the light source receiver 25 reaches its maximum. Therefore, when the light source is at its brightest, the thickness of the compensator is calculated using a micrometer reading. Substituting this into the formula, the refractive index of the liquid can be obtained. At this point, the thickness of the compensator corresponds to the refractive index of the liquid (i.e., the refractive index of the glass at this thickness matches the refractive index of the liquid). The change in the thickness of the compensator...The movement of interference fringes can be visually observed. The light source receiver 25 can be a mobile phone, which receives light signals through the phone's light sensor and combines the data provided by the mobile app to determine when the light source is brightest, thus determining the brightest value of the light source. Illuminance (E) is a physical quantity that measures the degree of illumination of an object's surface, usually expressed as the luminous flux received per unit illuminated area (I). Luminous intensity (I), on the other hand, reflects the spatial distribution of light, specifically measured by the luminous flux emitted by a point light source within a unit solid angle. It is worth noting that the illuminance of a point light source is inversely proportional to the square of the distance from the light source to the illuminated surface. Open the Phyphox app on the mobile phone and select the raw sensor "Light". Adjust the position of the phone's light sensor to align it as closely as possible with the center of the light source for subsequent experimental observation and data analysis. During each measurement, ensure that the count is as complete as possible to guarantee the accuracy of the experimental results. After each measurement, pause the measurement and prepare for the next measurement. Finally, the data exported from Phyphox was analyzed to further explore the relationship between light intensity and distance. The phone's built-in light sensor has excellent sensitivity, allowing the measurement results to be easily obtained directly through an Excel spreadsheet, saving the tedious manual counting and ensuring data accuracy.
[0023] t′ is the thickness of the narrow side of the first wedge glass plate 16, L is its length, θ is the angle of the wedge glass plate in degrees; d is the adjustment height of the second movable wedge glass plate 17, i.e. the reading of the micrometer screw gauge, t2 is the thickness of the compensator, and it can be known that the total thickness of the compensator t2=2t′+(Ld)tanθ. As we know from optical principles, when an object to be measured is placed in front of one of the double slits, the optical path length of the object changes, causing the central bright fringe on the screen to shift. Using a compensator-like device, the object is placed in front of the other slit, and the thickness of the compensator is adjusted using a micrometer screw gauge. This adjusts the optical path length of the light passing through that slit, and the central bright fringe moves accordingly. When the central bright fringe returns to its origin, the optical paths of the two light paths of the two slits are equal. Let the refractive index of air be n, the refractive index of the liquid to be measured be n1, and the refractive index of the compensator be n2. Then the relationship between the liquid to be measured and the thickness of the compensator is n1={n2t2+n(t1-t2)} / t1. Also, since t2=2t′+(Ld)tanθ, the refractive index of the liquid to be measured can be obtained simply by reading the micrometer screw gauge.
[0024] When the Phyphox light sensor in the mobile phone tests the light source.
[0025] The bottom of the sliding base 3 is symmetrically provided with slide grooves 4 corresponding to the slide rail 2, and the slide grooves 4 are engaged with the slide rail 2. The sliding base 3 can be moved by the cooperation of the slide rail 2 and the slide grooves 4.
[0026] The positioning mechanism includes a threaded ring 5 and a positioning bolt 6. The threaded ring 5 is fixedly installed on the sliding base 3, and the positioning bolt 6 is threaded inside the threaded ring 5. When positioning the sliding base 3, the positioning bolt 6 is rotated, and the positioning bolt 6 is moved through the threaded ring 5. After the positioning bolt 6 contacts the top of the base plate 1, the position of the sliding base 3 can be positioned, thereby achieving the purpose of adjusting and positioning the distance between the laser source 8, the beam expander 9, the adjustable single slit 10, the double slit plate 12, and the light source receiver 25.
[0027] The adjustment assembly includes a frame 15, a lateral adjustment mechanism, and a longitudinal adjustment mechanism. The frame 15 is fixedly installed on the side of the double-slit plate 12. The lateral adjustment mechanism and the longitudinal adjustment mechanism are located inside the frame 15. The position of the second wedge glass 17 can be adjusted through the lateral adjustment mechanism and the longitudinal adjustment mechanism, thereby changing the thickness of the compensator.
[0028] The lateral adjustment mechanism includes a first micrometer screw gauge 18, a knob 19, and a slider 20. The first micrometer screw gauge 18 is rotatably mounted inside the frame 15. The knob 19 is fixedly connected to one end of the first micrometer screw gauge 18. The slider 20 is slidably mounted inside the frame 15, and one end of the first micrometer screw gauge 18 is threadedly connected to the slider 20. The longitudinal adjustment mechanism includes a support block 21, a fixing ring 22, a second micrometer screw gauge 23, and a connecting block 27. One end of the support block 21 is fixedly connected to the slider 20. The fixing ring 22 is embedded inside the support block 21. The second micrometer screw gauge 23 is connected inside the fixing ring 22. The connecting block 27 is fixedly installed at the bottom of the second wedge-shaped glass 17. One end of the second micrometer screw gauge 23 is connected to a movable frame 24. A guide rod 26 is fixedly installed inside the movable frame 24 and passes through the connecting block 27. A pressure spring 28 is arranged around the guide rod 26. One end of the compression spring 28 is fixedly connected to the inner wall of the movable frame 24, and the other end of the compression spring 28 is fixedly connected to the connecting block 27. The threaded structure of the central part of the first screw micrometer 18 and the second screw micrometer 23 is responsible for moving and measuring within a small range. Its pitch determines the measurement accuracy (existing technology). Rotating the knob 19 will drive the first screw micrometer 18 to move. When the first screw micrometer 18 moves, it will push the slider 20 to move. Then, the slider 20 can be used to adjust the lateral position of the second wedge glass 17. Rotating the second screw micrometer 23 will push the movable frame 24 to move. Through the cooperation of the movable frame 24 and the connecting block 27, the longitudinal position of the second wedge glass 17 can be adjusted. At the same time, the compression spring 28 applies pressure to one side of the connecting block 27, which can adaptively adjust the position of the second wedge glass 17 so that the second wedge glass 17 fits tightly with the first wedge glass 16.
[0029] As a technical optimization of this utility model, when measuring the refractive index of a liquid using a liquid refractive index measuring device, the distance between the laser source 8, beam expander 9, adjustable single slit 10, double slit plate 12, and light source receiver 25 can be adjusted to a predetermined position by adjusting the position of the sliding base 3. The position of the sliding base 3 can then be positioned using a positioning mechanism, thereby positioning the laser source 8, beam expander 9, adjustable single slit 10, double slit plate 12, and light source receiver 25. Laser 8 emits a laser beam, which is expanded by beam expander 9, directing the light source toward adjustable single slit 10. The adjustable single slit 10 transforms the light source into a rectangle, directing it toward light slit 13. After passing through light slit 13, the light source is collected by light source receiver 25. As the light source passes through light slit 13, it first passes through cuvette 14, wedge-shaped glass 16, and wedge-shaped glass 17 positioned on one side. Wedge-shaped glass 16 and wedge-shaped glass 17 form a compensator-like device. An empty cuvette 14 and the compensator-like device are placed in front of the double slits. The compensator shifts the central bright fringe. The position of the second wedge glass 17 can be adjusted by adjusting the component, so that the second wedge glass 17 slides close to the inclined surface of the first wedge glass 16, changing its thickness and thus altering the optical path. The liquid to be tested is added into the empty cuvette 14. Both the compensator and the cuvette 14 are placed close to the light-entry side of the two light slits 13 and kept parallel to the double slits. Finally, the light source after passing through the compensator and the cuvette 14 is received by the light source receiver 25. When the compensator is adjusted to match the refractive index of the liquid in the cuvette 14, the brightness of the light source on the light source receiver 25 will reach its maximum. Therefore, when the light source is received at its brightest through the light source receiver 25, the thickness of the compensator can be calculated by taking a micrometer reading. Substituting this into the formula, the refractive index of the liquid can be obtained. At this time, the thickness of the compensator corresponds to the refractive index of the liquid (i.e., the refractive index reached by the glass at this thickness is the same as the refractive index of the liquid). The change in the thickness of the compensator can be used to visually reflect the movement of the interference fringes.
[0030] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0031] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A liquid refractive index measuring device, comprising a base plate (1), characterized in that: The base plate (1) is symmetrically provided with slide rails (2) on its top. Four sliding bases (3) are arranged in an array from left to right on the top of the slide rails (2). A bracket (7) is fixedly installed on the top of each sliding base (3). A positioning mechanism for positioning the sliding base (3) is provided on each sliding base (3). The four sliding bases (3) are sequentially fixedly connected from left to right to each other via the bracket (7) to a laser light source (8), a beam expander (9), a double-slit plate (12), an adjustable single slit (10), and a light source receiver (25). The laser light source (8), beam expander (9), double-slit plate (12), and adjustable single slit (10) are also connected in this manner. The double-slit plate (12) is aligned with the light source receiver (25) and has two light slits (13). A cuvette (14) and a first wedge glass (16) are fixedly connected to the side of the double-slit plate (12), and the cuvette (14) and the first wedge glass (16) are arranged parallel to each other on one side of the corresponding light slit (13). A second wedge glass (17) is provided on the side of the first wedge glass (16), and the inclined surfaces of the first wedge glass (16) and the second wedge glass (17) abut against each other. An adjustment component for adjusting the position of the second wedge glass (17) is provided on the double-slit plate (12).
2. The liquid refractive index measuring device as described in claim 1, characterized in that: The bottom of the sliding base (3) is symmetrically provided with sliding grooves (4) corresponding to the slide rail (2), and the sliding grooves (4) are engaged with the slide rail (2).
3. The liquid refractive index measuring device as described in claim 1, characterized in that: The positioning mechanism includes a threaded ring (5) and a positioning bolt (6). The threaded ring (5) is fixedly installed on the sliding base (3), and the positioning bolt (6) is threadedly connected inside the threaded ring (5).
4. The liquid refractive index measuring device as described in claim 1, characterized in that: The adjustment assembly includes a frame (15), a lateral adjustment mechanism and a longitudinal adjustment mechanism. The frame (15) is fixedly installed on the side of the double-seam plate (12), and the lateral adjustment mechanism and the longitudinal adjustment mechanism are located inside the frame (15).
5. The liquid refractive index measuring device as described in claim 4, characterized in that: The lateral adjustment mechanism includes a first micrometer screw gauge (18), a knob (19), and a slider (20). The first micrometer screw gauge (18) is set inside the frame (15). The side of the knob (19) is fixedly connected to one end of the first micrometer screw gauge (18). The slider (20) is slidably set inside the frame (15), and one end of the first micrometer screw gauge (18) is fixedly connected to the slider (20).
6. The liquid refractive index measuring device as described in claim 5, characterized in that: The longitudinal adjustment mechanism includes a support block (21), a fixing ring (22), a second micrometer screw gauge (23), and a connecting block (27). One end of the support block (21) is fixedly connected to the slider (20). The fixing ring (22) is embedded inside the support block (21). The second micrometer screw gauge (23) is connected inside the fixing ring (22). The connecting block (27) is fixedly installed at the bottom of the second wedge-shaped glass (17). One end of the second micrometer screw gauge (23) is connected to a movable frame (24). A guide rod (26) is fixedly installed inside the movable frame (24), and the guide rod (26) passes through the connecting block (27). A pressure spring (28) is arranged around the guide rod (26), and one end of the pressure spring (28) is fixedly connected to the inner wall of the movable frame (24), and the other end of the pressure spring (28) is fixedly connected to the connecting block (27).