A refractometer
Patent Information
- Application Number
- CN202610924950.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-06-25
- Publication Date
- 2026-09-25
AI Technical Summary
[0003]然而，发明人发现，在折光仪测量高温液体（例如60℃–100℃）时，液体温度远高于设备温度，需要等待数十秒甚至数分钟才能达到稳定液体温度与设备内部温度的平衡状态，严重限制了高温液体场景下的快速检测能力
[0013]本申请实施例中，通过将温度传感器的探头直接暴露于储液槽中，与储液槽内的待测液体发生直接物理接触，相较于在折光仪中设置内藏式的温度传感器，本申请实施例实现了零延迟热耦合，待测液体温度变化可瞬时传递至温度传感器，而且测量得到的温度即为当前参与折光的液体真实温度，而非现有折光仪中的设备结构温度；另外，折光仪内存储有针对不同温度区间的温度补偿模型，发明人通过实验发现，在不同的温度区间内折射率和温度的关系呈现不同特点，其中在低温区呈现出线性相关的特点，在高温区呈现出非线性相关的特点；通过在低温区设置对应的线性温度补偿模型，以及在高温区设置对应的非线性温度补偿模型，在得到待测液体实时准确的当前温度后，折光仪可以选择当前温度对应的温度补偿模型对待测液体的浓度值进行测量，能够得到准确度更高的浓度值。
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Figure CN122814539A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of optical testing instrument technology, specifically to a refractometer. Background Technology
[0002] A refractometer is an optical measuring instrument based on the principle of the critical angle of total internal reflection. Its core principle is that when light enters a liquid (which is an optically less dense medium) through a prism in an optically denser medium, light rays with an angle of incidence greater than the critical angle undergo total internal reflection. By capturing the light-dark boundary region formed at the optical interface, the refractive index of the liquid can be detected. The accuracy of the refractometer's refractive index measurement is affected by temperature. For the same liquid, changes in temperature alter the density of the medium, causing a shift in the critical angle and resulting in measurement errors in the refractive index. To address this, the inventors incorporated a temperature sensor on the prism within the refractometer. When the prism and the liquid reach temperature equilibrium, the temperature of the liquid is determined by checking the prism's temperature. Then, based on this temperature, a temperature compensation model is used to calculate refractive index compensation, bringing the refractive index of the liquid to the level at a preset temperature, thus avoiding measurement errors caused by measuring the refractive index at different temperatures.
[0003] However, the inventors discovered that when measuring high-temperature liquids (e.g., 60℃–100℃) with a refractometer, the liquid temperature is much higher than the equipment temperature. It takes tens of seconds or even minutes to reach a stable equilibrium between the liquid temperature and the internal temperature of the equipment, severely limiting the rapid detection capability in high-temperature liquid scenarios. Moreover, the inventors found that the degree of refractive index drift of liquids differs at high and low temperatures, and using the same temperature compensation model for compensation results in insufficient accuracy in calculating the concentration of the liquid being tested. Summary of the Invention
[0004] This invention aims to provide a refractometer. The refractometer includes a liquid storage tank for containing the liquid to be measured, a processing module, a light source module, a prism, a camera, a focusing module, a display screen, and a temperature sensor, wherein... The bottom surface of the liquid storage tank includes a light-transmitting area and a through hole. The prism and the temperature sensor are located on the back of the liquid storage tank. The back of the light-transmitting area abuts against the outer surface of the prism. The area on the outer surface of the prism that overlaps with the light-transmitting area is the detection area. The probe of the temperature sensor is located at the through hole and is used to directly detect the current temperature of the liquid to be tested in the liquid storage tank. The light source module is used to emit a light beam to the detection area of the prism. When at least part of the light beam undergoes total internal reflection at the detection area, the totally reflected light beam is incident on the converging module and converged to the camera. The camera is used to generate a detection image, on which a brightness abrupt change boundary is formed. The processing module is used to determine the initial refractive index of the liquid to be tested based on the position of the brightness abrupt change boundary on the detection image. The refractometer also stores at least two temperature compensation models corresponding to at least two temperature ranges. The processing module is further configured to select the corresponding temperature compensation model based on the current temperature detected by the temperature sensor, and to calculate the concentration value of the liquid to be tested based on the current temperature, the initial refractive index, and the temperature compensation model. The concentration value of the liquid to be tested is the concentration value corresponding to the refractive index of the liquid to be tested at 20 degrees Celsius. The display screen is used to display the concentration value of the liquid to be tested. The at least two temperature ranges include a first temperature range below 45 degrees and a second temperature range above 45 degrees. The two temperature compensation models include a first temperature compensation model corresponding to the first temperature range and a second temperature compensation model corresponding to the second temperature range. The first temperature compensation model is a linear model, and the second temperature compensation model is a nonlinear model.
[0005] Optionally, the display screen is also used to receive the weight of coffee powder and coffee liquid input by the user; The processing module is also used to calculate the extraction rate of the liquid to be tested based on the concentration value of the liquid to be tested, the weight of the coffee powder, and the weight of the coffee liquid; The display screen is also used to display the extraction rate of the liquid to be tested.
[0006] Optionally, the display screen is also used to display a gold cup extraction graph, wherein one of the horizontal and vertical axes of the gold cup extraction graph represents the concentration value and the other represents the extraction rate; The display screen is also used to display the concentration value and extraction rate of the liquid to be tested, and their positions in the gold cup extraction graph.
[0007] Optionally, the refractometer also provides a continuous measurement mode, in which the display screen is used to display at least one of the following: The most recent concentration value; The total number of measurements up to the current time after entering continuous measurement mode; The average concentration value up to the current measurement after entering continuous measurement mode; A graph showing the concentration values obtained from multiple measurements up to the current point after entering continuous measurement mode.
[0008] Optionally, the refractometer also includes a dust cover for removably covering the liquid storage tank; The dust cover is made of metal.
[0009] Optionally, the dust cover has an active cooling function, which is used to cool the liquid to be tested in the liquid storage tank when it is placed on the liquid storage tank; The dust cover is also used to stop the cooling function when the temperature of the liquid to be tested reaches the target temperature, wherein the target temperature is not higher than 45 degrees.
[0010] Optionally, the refractometer is further equipped with a sensor for detecting the current light intensity inside the refractometer; The processing module is also used to compensate for the position of the brightness abrupt change boundary based on the difference between the current light intensity and the preset light intensity, and to determine the initial refractive index of the liquid to be tested based on the position of the compensated brightness abrupt change boundary.
[0011] Optionally, the refractometer is also used to enter a zero-calibration mode according to the user's operation. In the zero-calibration mode, the refractometer is used to detect the concentration value of the clean water added by the user to the storage tank, and to use the detected concentration value of the clean water as the reference zero point for subsequent concentration detection.
[0012] Optionally, the refractometer further includes a rear cover and a front cover; the front cover has a first through hole and a second through hole arranged in parallel, and the front cover and the rear cover are used to seal the processing module, the light source module, the prism, the camera and the converging module between the rear cover and the front cover; The first through hole of the front cover presses against the periphery of the opening of the liquid storage tank, and the second through hole of the front cover presses against the periphery of the display screen.
[0013] In this embodiment, by directly exposing the temperature sensor probe to the liquid reservoir, allowing direct physical contact with the liquid being tested, this embodiment achieves zero-delay thermal coupling compared to a built-in temperature sensor within the refractometer. Temperature changes in the liquid being tested are instantly transmitted to the temperature sensor, and the measured temperature is the true temperature of the liquid currently participating in refraction, rather than the structural temperature of the existing refractometer. Furthermore, the refractometer stores temperature compensation models for different temperature ranges. The inventors discovered through experiments that the relationship between refractive index and temperature exhibits different characteristics in different temperature ranges, showing a linear correlation in the low-temperature range and a non-linear correlation in the high-temperature range. By setting corresponding linear temperature compensation models in the low-temperature range and corresponding non-linear temperature compensation models in the high-temperature range, after obtaining the real-time and accurate current temperature of the liquid being tested, the refractometer can select the temperature compensation model corresponding to the current temperature to measure the concentration value of the liquid being tested, resulting in a more accurate concentration value. Attached Figure Description
[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0015] Figure 1 This is a schematic diagram of the external structure of one embodiment of the refractometer of this application; Figure 2 This is a schematic diagram showing the positional relationship of the light source module, prism, and camera in an example of the refractometer of this application; Figure 3 yes Figure 1 A partial exploded view of one embodiment of the refractometer shown; Figure 4 This is a schematic diagram of another embodiment of the refractometer described in this application; Figure 5 yes Figure 3 A schematic diagram of the front cover from another perspective in the illustrated embodiment; Figure 6 This is a schematic diagram of an embodiment of the interactive interface on the display screen of the refractometer of this application; Figure 7 This is a schematic diagram of an embodiment of the interactive interface displayed on the screen of the refractometer when it enters continuous measurement mode in this application. Figure 8This is a schematic diagram of an embodiment of the interactive interface displayed on the screen of the refractometer in continuous measurement mode according to the present application. Detailed Implementation
[0016] To further illustrate the various embodiments, the present invention provides accompanying drawings. These drawings are part of the disclosure of the present invention, primarily used to illustrate the embodiments and to explain the operating principles of the embodiments in conjunction with the relevant descriptions in the specification. With reference to these drawings, those skilled in the art should be able to understand other possible implementations and the advantages of the present invention. Components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.
[0017] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. For example... Figure 1 As shown, Figure 1 This is a schematic diagram of the external structure of an embodiment of the refractometer of this application. The refractometer 10 includes a liquid storage tank 11, a light source module, a prism, a camera, a display screen 15, a temperature sensor 16, a focusing module, and a processing module. The prism 13 and the temperature sensor 16 are located on the back side of the liquid storage tank 11. The bottom surface of the liquid storage tank 11 includes a light-transmitting area 111 and a through hole 112. The light-transmitting area 11 can be a through hole or a bottom surface made of a light-transmitting material. The back side of the light-transmitting area 111 of the liquid storage tank 11 abuts against the outer surface of the prism 13, and the area on the outer surface of the prism 13 that overlaps with the light-transmitting area 111 is the detection area. Optionally, the other areas surrounding the detection area on the outer surface of the prism 13 are coated with adhesive to fix the prism 13 and the bottom of the liquid storage tank 11 to each other.
[0018] like Figure 2 As shown, Figure 2 This is a schematic diagram showing the positional relationship of the light source module, prism, and camera in an example of the refractometer of this application. The light source module 12 is used to emit a light beam to the detection area 131 of the prism 13. When the liquid tank 11 contains the liquid to be tested, and the liquid to be tested and the prism 13 satisfy the total internal reflection condition, the light beam emitted by the light source module 12 to the detection area of the prism 13 that satisfies the total internal reflection condition is totally reflected at the detection area to the converging module 17, and the light beam that does not satisfy the total internal reflection condition is transmitted out from the detection area. The converging module 17 is used to converge the totally reflected light beam at the detection area to the camera 14 located on the focal plane of the converging module 17. The camera is used to generate a photosensitive image. The converging module 17 can be a lens, in which case the focal plane of the converging module 17 refers to the focal plane of the lens; or it can be a lens group consisting of at least two lenses, in which case the focal plane of the converging module 17 is the equivalent focal plane of the lens group. In the scheme using a lens group, the aberrations and distortions of the image formed by the converging module can also be reduced through the optical design of the lens.
[0019] The function of the converging module is explained below using a lens as an example. Ideally, parallel light can be converged by a lens to a converging point on the focal plane. This converging point is the intersection point where the parallel light extends from the optical center of the lens along the direction of the light and intersects the focal plane. Therefore, this converging point depends only on the direction of the light and is independent of the light's exit position. Utilizing this principle, this embodiment decouples the position and direction of light by setting a converging module in front of the camera. This ensures that in any plane passing through the optical center of the converging module, light rays that are totally reflected at different positions of the reflection module with the same exit angle will be converged to the same position on the photosensitive array within the camera, ultimately forming a brightness abrupt change boundary line corresponding to the total internal reflection angle on the photosensitive array. Due to the setting of the converging module, different positions of the brightness abrupt change boundary line in the detected image correspond to light beams that are totally reflected at different total internal reflection angles. Therefore, the processing module can determine the total internal reflection angle corresponding to the brightness abrupt change boundary line by obtaining its position, and then calculate the initial refractive index of the liquid being tested based on this total internal reflection angle.
[0020] like Figure 1 As shown, the probe of the temperature detector 16 is located at the through hole 112 of the liquid storage tank 11, and is used to directly detect the temperature of the liquid to be tested in the liquid storage tank. In some examples, the temperature sensor is a contact-type PT100 platinum resistance temperature sensor. The refractometer also stores at least two temperature compensation models corresponding to at least two temperature ranges respectively. The processing module is also used to select the corresponding temperature compensation model according to the current temperature detected by the temperature sensor, and to calculate the concentration value of the liquid to be tested according to the current temperature, the initial refractive index and the temperature compensation model. Optionally, the concentration value of the liquid to be tested is specifically the total dissolved solids (TDS). Optionally, the concentration value of the liquid to be tested is the concentration value corresponding to the refractive index of the liquid to be tested at 20 degrees Celsius. The at least two temperature ranges include a first temperature range below 45 degrees Celsius and a second temperature range above 45 degrees Celsius. The two temperature compensation models include a first temperature compensation model corresponding to the first temperature range and a second temperature compensation model corresponding to the second temperature range. The first temperature compensation model is a linear model, and the second temperature compensation model is a nonlinear model. The processing module is further configured to calculate the concentration value of the liquid to be tested based on the target refractive index; the display screen is used to display the concentration value of the liquid to be tested.
[0021] Optionally, the temperature sensor continuously measures the current temperature of the liquid to be tested in the storage tank at a first frequency, the camera continuously generates an image of the liquid to be tested at a second frequency, the processing module continuously calculates the concentration value of the liquid to be tested based on the latest measured current temperature of the liquid to be tested and the position of the brightness change boundary in the latest generated image of the liquid to be tested at a third frequency, and the display screen displays the latest concentration value calculated by the processing module at a fourth frequency. Optionally, any two of the first, second, third, and fourth frequencies can be the same or different.
[0022] In this embodiment, by directly exposing the temperature sensor probe to the liquid reservoir, allowing direct physical contact with the liquid being tested, this embodiment achieves zero-delay thermal coupling compared to a built-in temperature sensor within the refractometer. Temperature changes in the liquid being tested are instantly transmitted to the temperature sensor, and the measured temperature is the true temperature of the liquid currently participating in refraction, rather than the structural temperature of the existing refractometer. Furthermore, the refractometer stores temperature compensation models for different temperature ranges. The inventors discovered through experiments that the relationship between refractive index and temperature exhibits different characteristics in different temperature ranges, showing a linear correlation in the low-temperature range and a non-linear correlation in the high-temperature range. By setting corresponding linear temperature compensation models in the low-temperature range and corresponding non-linear temperature compensation models in the high-temperature range, after obtaining the real-time and accurate current temperature of the liquid being tested, the refractometer can select the temperature compensation model corresponding to the current temperature to measure the concentration value of the liquid being tested, resulting in a more accurate concentration value.
[0023] In some examples, the first temperature range is 0 to 45 degrees Celsius, or 0 to 40 degrees Celsius. In some examples, the second temperature range is above 45 degrees Celsius, or above 60 degrees Celsius. In some examples, the refractometer only stores temperature compensation models corresponding to two temperature ranges, for example, only storing temperature compensation models corresponding to temperature ranges no greater than 45 degrees Celsius and temperature ranges greater than 45 degrees Celsius. In some examples, the refractometer stores three or more temperature ranges and their corresponding temperature compensation models, for example, temperature compensation models corresponding to the three temperature ranges of 0-40 degrees Celsius, 40-60 degrees Celsius, and 60-100 degrees Celsius respectively.
[0024] In some examples, the first temperature compensation model is n1 = n + k × (T - 20), where n1 is the refractive index of the liquid under test at a standard temperature of 20 degrees Celsius; T is the current temperature measured by the temperature sensor; n is the initial refractive index calculated based on the current temperature T of the liquid under test, and this current temperature is within a first temperature range; k is a pre-calibrated coefficient. Optionally, the refractometer also stores a relationship model between the refractive index and concentration value of the liquid under test at 20 degrees Celsius, and the processing module calculates the concentration value based on this relationship model and the refractive index n1. This relationship model can be calibrated using a linear model, a quadratic polynomial model, or a cubic polynomial model. In some examples, this relationship model is C = a × n1 + b; where C is the liquid concentration value, and a and b are coefficients obtained through calibration. In some examples, the second temperature compensation model is C = C0 + a × (T - 20). 20)+b× dT / dt +c×(T T1), where C0 is the initial concentration value calculated by the processing module based on the initial refractive index n; T is the current temperature of the liquid to be tested, which is within the second temperature range; dT / dt is the current cooling rate; T1 is the current temperature of the refractometer; a, b and c are the model coefficients obtained through calibration.
[0025] like Figure 3 As shown, Figure 3 yes Figure 1 The diagram shows a partial exploded view of one embodiment of the refractometer. The refractometer also includes a rear cover 31 and a front cover 32; the front cover 32 has a first through hole 321 and a second through hole 322 arranged side-by-side. The front cover 32 and the rear cover 31 are used to seal the processing module, the light source module, the prism, the camera, and the focusing module between the rear cover and the front cover. Figure 3As shown, in a specific example, the first through-hole 321 of the front cover abuts against the periphery of the opening of the liquid storage tank 16, and the second through-hole 322 of the front cover abuts against the periphery of the display screen 15, so that the rear cover 31 and the front cover 32 seal the processing module, the light source module, the prism, the camera, the converging module, and the temperature sensor between the rear cover 31 and the front cover 32. Optionally, a button 33 is also provided on one side of the display screen 15 for user interaction with the refractometer. Optionally, the front cover 32 is an aluminum alloy front cover. Aluminum has excellent thermal conductivity, which can quickly transfer the internal heat of the battery, chip, etc., to the front cover for release, avoiding excessive internal temperature that could cause performance and lifespan degradation. Optionally, thermally conductive adhesive is also applied to the back of the camera, and it is pressed together with an aluminum heat sink; since the camera generates heat, this can quickly transfer the camera heat to the aluminum heat sink, stabilizing the camera's operating temperature. Optionally, the rear cover uses a custom-made rubber ring for sealing, and there are no screw holes inside the rubber ring that communicate with the outside, achieving an effective waterproof effect. Alternatively, the rubber ring can use a bimodal ridge, i.e., a line seal, which can achieve a sealing effect under less pressure.
[0026] Optionally, the liquid reservoir 16 is made of metal, which allows for rapid cooling of the liquid being tested. For example... Figure 4 As shown, Figure 4 This is a schematic diagram of another embodiment of the refractometer described in this application. (And...) Figure 1 Unlike the refractometer shown, the refractometer 40 also includes a dust cover 41, which is detachably mounted on the liquid storage tank. The dust cover is made of metal and, when in place, fits tightly against the edge of the liquid tank, allowing heat to be quickly transferred to the outer cover and dissipated to the outside, thus enabling the liquid to be tested to cool rapidly. Figure 5 As shown, Figure 5 yes Figure 3 The illustrated embodiment shows a structural schematic diagram of the front cover from another perspective. Optionally, the fixing position 51 where the front cover 32 presses against the periphery of the liquid storage tank opening is provided with four circular recesses 52 surrounding the liquid storage tank opening, and four strong magnets are fixed in the circular recesses; a stainless steel ring is embedded inside the dust cover, so that the dust cover can be attracted to the magnets and firmly attached to the liquid tank. Optionally, the outer periphery of the dust cover is also provided with multiple concentric circular patterns, which can increase the friction force when gripped and increase the heat dissipation area.
[0027] Optionally, the dust cover has an active cooling function to cool the liquid being tested in the storage tank when it is placed over the tank. The dust cover also stops the cooling function when the temperature of the liquid being tested reaches a target temperature, wherein the target temperature is not higher than 45 degrees Celsius. For example, the dust cover contains a cooling element that can drive the cooling function. The dust cover can also communicate with the refractometer body; when the refractometer detects that the temperature of the liquid being tested has dropped to the 0-45°C range, it sends a command to the dust cover to stop the cooling function. Optionally, the refractometer body is also provided with a power interface for connecting to the power interface for power supply when the dust cover is on the storage tank. Optionally, the refractometer can stop the cooling function of the dust cover by cutting off power when it detects that the temperature of the liquid being tested has dropped to the 0-45°C range.
[0028] The inventors discovered through experiments that the accuracy of the concentration value calculated by the temperature compensation model for liquids below 45 degrees Celsius is higher than that calculated for liquids above 45 degrees Celsius. Rapidly cooling the liquid to below 45 degrees Celsius using a storage tank and dust cover, and then using the first temperature compensation model to calculate the concentration value, can help obtain a more accurate concentration value.
[0029] In some examples, the display screen is also used to receive the weight of coffee powder and the weight of coffee liquid input by the user; the processing module is also used to calculate the extraction rate of the liquid to be tested based on the concentration value of the liquid to be tested, the weight of the coffee powder, and the weight of the coffee liquid; the display screen is also used to display the extraction rate of the liquid to be tested. Figure 6 As shown, Figure 6 This is a schematic diagram of an embodiment of the interactive interface on the display screen of the refractometer of this application. The display screen shows a gold cup extraction plot, which includes a two-dimensional coordinate axis, wherein one of the horizontal and vertical axes of the two-dimensional coordinate axis represents the concentration value and the other represents the extraction rate. The display screen is also used to display the concentration value and extraction rate of the liquid to be tested at position 61 in the gold cup extraction plot. Optionally, the display screen displays the gold cup extraction... Figure 1 The side also displays at least one of the following: concentration of the liquid being tested, weight of coffee powder, weight of coffee liquid, and extraction rate.
[0030] In some examples, the refractometer also provides a continuous measurement mode, in which the display screen is used to display at least one of the following: the most recently measured concentration value, the total number of measurements up to the current time since entering the continuous measurement mode, the average concentration value up to the current time since entering the continuous measurement mode, and a graph corresponding to the concentration values obtained from multiple measurements up to the current time since entering the continuous measurement mode. Figure 7 As shown, Figure 7This is a schematic diagram of an embodiment of the interactive interface displayed on the screen of the refractometer when it enters continuous measurement mode according to this application. The interface displays the concentration value 71 obtained from the current measurement, and shows two options: option 72 to add a test and option 73 to open a new test. When the user selects option 72, the refractometer enters continuous measurement mode. Figure 8 As shown, Figure 8 This is a schematic diagram of an embodiment of the interactive interface displayed on the screen of the refractometer in continuous measurement mode according to this application. In this mode, the left side of the interactive interface displayed on the screen shows the latest concentration value measurement result 81, and the right side shows the total number of measurements up to the current time since entering continuous measurement mode 82 and the average value 83 of the multiple measurements corresponding to the total number of measurements. The bottom of the screen also displays the curve 84 corresponding to the concentration values obtained from the multiple measurements corresponding to the total number of measurements.
[0031] In some examples, the refractometer is further equipped with a sensor to detect the current light intensity within the refractometer; the processing module is also used to compensate for the position of the brightness abrupt change boundary based on the difference between the current light intensity and a preset light intensity, and to determine the initial refractive index of the liquid to be tested based on the compensated position of the brightness abrupt change boundary. In one example, the refractometer stores a compensation model, for example, the compensation model is offset D = f(L-L1), where D is the offset, L is the current light intensity, and L1 is the preset light intensity. After calculating the difference between the current light intensity and the preset light intensity, the processing module uses the compensation model to calculate the offset, and then uses the offset to compensate for the position of the brightness abrupt change boundary.
[0032] In some examples, the refractometer is also used to enter a zero-calibration mode according to the user's operation. In the zero-calibration mode, the refractometer is used to detect the concentration value of the clean water added by the user to the storage tank, and to use the detected concentration value of the clean water as the reference zero point for subsequent concentration detection.
[0033] In some embodiments, the system and its modules can be implemented by hardware, software, or a combination of both. The hardware portion can be implemented using dedicated logic; the software portion can be stored in memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated-design hardware. Those skilled in the art will understand that the methods and systems described above can be implemented using computer-executable instructions and / or included in the control code of a processor, such as on a media such as a disk, CD, or DVD-ROM, or in the memory of a programmable device. The systems and modules of this specification can be implemented not only by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips or transistors, or programmable hardware devices such as field-programmable gate arrays or programmable logic devices, but also by software, for example, executed by various types of processors, or by a combination of the aforementioned hardware circuits and software (e.g., firmware).
[0034] It should be noted that the above description of the system and its modules is for convenience only and should not be construed as limiting this specification to the embodiments described. It is understood that those skilled in the art, after understanding the principles of this system, may arbitrarily combine the various modules without departing from these principles to form subsystems connected to other modules. Alternatively, some modules may be split to obtain more modules or multiple units under a single module. Such modifications are all within the scope of this specification.
[0035] The basic concepts have been described above. It is obvious that the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, various modifications, improvements, and corrections may be made to this specification by those skilled in the art. Such modifications, improvements, and corrections are taught in this specification and therefore remain within the spirit and scope of the exemplary embodiments described herein.
Claims
1. A refractometer, characterized in that: It includes a liquid storage tank for containing the liquid to be tested, a processing module, a light source module, a prism, a camera, a focusing module, a display screen, and a temperature sensor, among which, The bottom surface of the liquid storage tank includes a light-transmitting area and a through hole. The prism and the temperature sensor are located on the back of the liquid storage tank. The back of the light-transmitting area abuts against the outer surface of the prism. The area on the outer surface of the prism that overlaps with the light-transmitting area is the detection area. The probe of the temperature sensor is located at the through hole and is used to directly detect the current temperature of the liquid to be tested in the liquid storage tank. The light source module is used to emit a light beam to the detection area of the prism. When at least part of the light beam undergoes total internal reflection at the detection area, the totally reflected light beam is incident on the converging module and converged to the camera. The camera is used to generate a detection image, on which a brightness abrupt change boundary is formed. The processing module is used to determine the initial refractive index of the liquid to be tested based on the position of the brightness abrupt change boundary on the detection image. The refractometer also stores at least two temperature compensation models corresponding to at least two temperature ranges. The processing module is further configured to select the corresponding temperature compensation model based on the current temperature detected by the temperature sensor, and to calculate the concentration value of the liquid to be tested based on the current temperature, the initial refractive index, and the temperature compensation model. The concentration value of the liquid to be tested is the concentration value corresponding to the refractive index of the liquid to be tested at 20 degrees Celsius. The display screen is used to display the concentration value of the liquid to be tested. The at least two temperature ranges include a first temperature range below 45 degrees and a second temperature range above 45 degrees. The two temperature compensation models include a first temperature compensation model corresponding to the first temperature range and a second temperature compensation model corresponding to the second temperature range. The first temperature compensation model is a linear model, and the second temperature compensation model is a nonlinear model.
2. The refractometer according to claim 1, characterized in that... The display screen is also used to receive the weight of coffee powder and coffee liquid input by the user; The processing module is also used to calculate the extraction rate of the liquid to be tested based on the concentration value of the liquid to be tested, the weight of the coffee powder, and the weight of the coffee liquid; The display screen is also used to display the extraction rate of the liquid to be tested.
3. The refractometer according to claim 2, characterized in that... The display screen is also used to display a gold cup extraction graph, wherein one of the horizontal and vertical axes of the gold cup extraction graph represents the concentration value and the other represents the extraction rate; The display screen is also used to display the concentration value and extraction rate of the liquid to be tested, and their positions in the gold cup extraction graph.
4. The refractometer according to claim 2, characterized in that, The refractometer also provides a continuous measurement mode, in which the display screen is used to display at least one of the following: The most recent concentration value; The total number of measurements up to the current time after entering continuous measurement mode; The average concentration value up to the current measurement after entering continuous measurement mode; A graph showing the concentration values obtained from multiple measurements up to the current point after entering continuous measurement mode.
5. The refractometer according to claim 1, characterized in that, The refractometer also includes a dust cover for removable installation on the liquid storage tank; The dust cover is made of metal.
6. The refractometer according to claim 5, characterized in that, The dust cover has an active cooling function, which is used to cool the liquid to be tested in the liquid storage tank when it is placed on the liquid storage tank. The dust cover is also used to stop the cooling function when the temperature of the liquid to be tested reaches the target temperature, wherein the target temperature is not higher than 45 degrees.
7. The refractometer according to claim 1, characterized in that, The refractometer is also equipped with a sensor for detecting the current light intensity inside the refractometer; The processing module is also used to compensate for the position of the brightness abrupt change boundary based on the difference between the current light intensity and the preset light intensity, and to determine the initial refractive index of the liquid to be tested based on the position of the compensated brightness abrupt change boundary.
8. The refractometer according to claim 1, characterized in that, The refractometer is also used to enter a zero-calibration mode according to the user's operation. In the zero-calibration mode, the refractometer is used to detect the concentration value of the clean water added by the user in the storage tank, and to use the detected concentration value of the clean water as the reference zero point for subsequent concentration detection.
9. The refractometer according to claim 1, characterized in that, The refractometer also includes a rear cover and a front cover; the front cover has a first through hole and a second through hole arranged in parallel, and the front cover and the rear cover are used to seal the processing module, the light source module, the prism, the camera and the focusing module between the rear cover and the front cover; The first through hole of the front cover presses against the periphery of the opening of the liquid storage tank, and the second through hole of the front cover presses against the periphery of the display screen.