CN110398476B - Pen-type layout optical system for measuring refractive index of liquid and measuring method thereof - Google Patents
Pen-type layout optical system for measuring refractive index of liquid and measuring method thereof Download PDFInfo
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- CN110398476B CN110398476B CN201910675821.8A CN201910675821A CN110398476B CN 110398476 B CN110398476 B CN 110398476B CN 201910675821 A CN201910675821 A CN 201910675821A CN 110398476 B CN110398476 B CN 110398476B
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- 239000000523 sample Substances 0.000 claims abstract description 46
- 238000005259 measurement Methods 0.000 claims abstract description 25
- 238000003384 imaging method Methods 0.000 claims description 7
- 238000000691 measurement method Methods 0.000 claims description 4
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
- G01N21/43—Refractivity; Phase-affecting properties, e.g. optical path length by measuring critical angle
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
- G01N21/4133—Refractometers, e.g. differential
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Abstract
The invention discloses an optical system for pen-type layout of liquid refractive index measurement and a measuring method thereof, wherein the optical system comprises a light source for generating light beams, a probe body for refracting incident light beams and an image sensor for receiving emergent light images, the probe body comprises a light inlet surface capable of enabling the light beams generated by the light source to enter an emergent light beam, a first reflecting surface for reflecting the emergent light beams of the light inlet surface, a working surface for converging the light beams reflected by the first reflecting surface and transmitting and/or emitting light, a second reflecting surface for reflecting the light beams reflected by the working surface, and an emergent surface for emitting the light beams reflected by the second reflecting surface; the measuring method adopts the light source to pass through the probe body, converges on the working surface, combines the transmission or/and reflection principle, utilizes the image sensor to receive the emergent light of the probe body, integrates the probe, the light source, the image sensor and the like into a whole, and can be used for measuring the refractive index of liquid.
Description
Technical Field
The invention relates to the technical field of measurement, in particular to an optical system with pen-type layout for measuring the refractive index of liquid and a measuring method thereof.
Background
In the prior art, the refractive index is one of important optical parameters of a liquid, and by means of the refractive index, the optical performance, purity, concentration, dispersion and other properties of the liquid can be known, and other parameters (such as temperature) are closely related to the refractive index. Therefore, the measurement of the refractive index of a liquid is of great importance in the fields of chemical industry, medicine, food, petroleum and the like. In particular, with the improvement of living standard and the enhancement of health consciousness, the requirements of people on food safety and food quality are also higher. The liquid refractive index measuring instrument can measure the refractive index of liquid food, and can compare the concentration of the liquid food under the support of big data, so that the sugar content, the acid content, the fat content and the like of the liquid food can be known, and the liquid refractive index measuring instrument plays a role in guiding eating of people, particularly sub-healthy people. Can also perform the identification function for special valuable and easy-to-imitate liquid beverages, such as famous wine, etc. In the health care industry, the method can be used for measuring the concentration of human excreta and monitoring the health index.
The total reflection critical angle imaging method is a commonly used method for measuring the refractive index of liquid, and calculates the refractive index of the liquid to be measured by measuring the emergence angle of light rays at a critical angle according to the total reflection principle. As shown in fig. 1, a typical total reflection critical angle measurement system includes a light source U1, a prism U3, and an image sensor U2, and in operation, a light beam emitted from the light source U1 passes through the prism U3 to reach an interface between a measured liquid X and the prism U3, where the light beam is separated into refracted light and reflected light, where the reflected light is received by the image sensor U2, and a bright-dark image as shown in the figure is generated. In the bright-dark image, the bright portion corresponds to the light totally reflected at the interface between the liquid X to be measured and the prism U3, the dark portion corresponds to the light not totally reflected, and the bright-dark cut-off corresponds to the critical angle at which total reflection occurs. Since the change in the refractive index of the measured liquid causes a change in the critical angle for total reflection, the critical angle for total reflection can be obtained by measuring the position of the cut-off, and the refractive index of the measured liquid can be obtained.
However, the conventional optical refractometer is large and cumbersome to operate, and the digital refractometer can be measured by one key, but has high cost and is not portable. Both are not easily generalized in the general population.
Disclosure of Invention
The invention aims to provide an optical system with pen-type layout for measuring the refractive index of liquid and a measuring method thereof, wherein the optical system integrates a probe, a light source, an image sensor and the like into a whole to form a miniaturized optical system which can be used for measuring the refractive index of the liquid; the light beam is collected on the working surface, so that the effective area is small, and the probe is designed in a working mode similar to a point, thereby the volume of the whole system can be designed to be smaller; the measuring method can be used for measuring the refractive index of the liquid, and the characterization of the concentration of the liquid is performed through the measurement of the refractive index.
The invention is realized by the following technical scheme: an optical system for pen-type layout of refractive index measurement of a liquid, comprising a light source for generating a light beam, a probe body for refracting an incident light beam, and an image sensor for receiving an image of the outgoing light, the probe body comprising:
a light beam generated by the light source can enter and form a light inlet surface of an emergent light beam,
a first reflecting surface for reflecting the light beam emitted from the light inlet surface,
the light beams reflected by the first reflecting surface are converged to form a working surface of an effective area which approximates a point, and when the working surface contacts the measured liquid, light collected at different angles in the effective area is transmitted and/or totally reflected,
a second reflecting surface for reflecting the light beam totally reflected by the working surface again,
and shaping the light beam reflected by the second reflecting surface and then emitting the shaped light beam to an emitting surface outside the probe body.
Further in order to better realize the invention, the following arrangement structure is adopted: and a deflection prism is arranged between the emergent end of the emergent surface and the image sensor.
Further in order to better realize the invention, the following arrangement structure is adopted: an eyepiece is also provided between the deflection prism and the image sensor.
Further in order to better realize the invention, the following arrangement structure is adopted: the eyepiece consists of two optical aspheres.
Further in order to better realize the invention, the following arrangement structure is adopted: the working face is converged at the central part of the working plane when the light beams are converged.
Further in order to better realize the invention, the following arrangement structure is adopted: the size of the converging light beam at the central part of the working surface is 0-1 mm.
Further in order to better realize the invention, the following arrangement structure is adopted: the light beam reflected by the second reflecting surface is parallel to the optical axis of the emergent light beam of the light inlet surface.
Further in order to better realize the invention, the following arrangement structure is adopted: the first reflecting surface and the second reflecting surface are arranged in mirror symmetry relative to the central line of the probe body.
Further in order to better realize the invention, the following arrangement structure is adopted: the first reflecting surface and the second reflecting surface adopt plane reflecting mirrors of total reflection (total reflection principle) or specular reflection (metal or dielectric reflecting film).
Further in order to better realize the invention, the following arrangement structure is adopted: the emergent surface is an optical aspheric lens.
Further in order to better realize the invention, the following arrangement structure is adopted: the refractive index of the working surface is 1.52-1.70.
Further in order to better realize the invention, the following arrangement structure is adopted: the incident surface is an optical aspheric lens.
Further in order to better realize the invention, the following arrangement structure is adopted: the probe body is also provided with a connecting pin.
Further in order to better realize the invention, the following arrangement structure is adopted: the probe body adopts an integrated structure.
A method of measuring an optical system for a pen-type arrangement for refractive index measurement of a liquid, comprising the steps of:
1) The light source generates incident light and projects the incident light to the first reflecting surface through the light inlet surface;
2) The first reflecting surface performs total reflection or specular reflection and reflects the reflected light to the working surface;
3) The working surface converges the light reflected by the first reflecting surface, part of the converged light beam is transmitted out from the measured liquid, and the rest light beams are totally reflected to the second reflecting surface;
4) The second reflecting surface projects the light beam reflected by the working surface to the emergent surface in a total reflection or specular reflection mode;
5) The emergent face transmits the light beam projected by the second reflecting face to the image sensor.
Further, in order to better implement the measuring method of the optical system for pen-type layout for measuring the refractive index of the liquid, the emergent surface also moves the optical axis of the light beam to the central axis through the deflection prism before transmitting the light beam projected by the second reflecting surface to the image sensor.
Further, in order to better realize the measuring method of the pen-type layout optical system for measuring the refractive index of the liquid, the light beam passing through the deflection prism is subjected to imaging and light intensity homogenization treatment through an eyepiece, and then is input to an image sensor.
In particular, in the present technical solution, terms such as "connection", "fixing", "setting", "movable connection", "movable setting", etc. related to the mechanical structure are all technical means for conventional setting in the mechanical field, and may be adopted as long as the purposes of fixing, connecting or movable setting can be achieved, so that the present invention is not limited in detail (for example, the present invention uses nuts and screws to perform movable or fixed connection, uses bolts to perform movable or fixed connection, sets, and realizes detachable connection between the a object and the B object by means of clamping).
Compared with the prior art, the invention has the following advantages:
(1) The invention preferably integrates a probe, a light source, a deflection prism, an ocular lens, an image sensor and the like into a whole by adopting pen-type layout (all devices are uniformly distributed on two sides of the central axis of the optical system), so as to form a miniaturized optical system, and the invention can be used for measuring the refractive index of liquid. The probe is designed by adopting a working mode that the light beam is concentrated on the working surface, so that the effective area is small and approximates to a point, thereby the volume of the whole system can be designed to be smaller.
(2) The invention can make the light beam gather on the working surface, make the effective area small and approximate to a point, thus the volume of the whole probe can be designed smaller.
(3) The probe is manufactured by adopting a compression molding process of a resin material, and the spherical surface, the aspherical surface and the plane are integrated into a whole at the same time, so that the whole probe is more miniaturized.
(4) The structure of the invention achieves further miniaturization, and can be applied to the measurement of precious samples, thereby reducing the loss of the measured liquid.
(5) The integration of the optical device in the invention is the basis of miniaturization of products, and the compression molding process of the resin material enables the integration of the optical device. Conventional glass optical devices are limited by the processing technology, and it is difficult to integrate spherical surfaces, aspherical surfaces and flat surfaces into one device at the same time, and it is also difficult to integrate optical surfaces and mounting structures together. And the resin device can be molded, so that various complex optical surfaces and assembly structures can be integrated into one device.
(6) The invention adopts the aspheric surface to collect the light of the surface light source LED and generate a working angle, and the traditional refractometer uses a plane to absorb the light emitted by the light source. The invention can miniaturize the light path and design working angles according to different differences of measuring range and precision. The design is more modularized, and under the condition that other parts of the system are unchanged, the design of the light inlet surface is changed, so that measurement with different precision and measuring range can be realized.
(7) Since the light emitted by the probe is deflected to one side of the system, if the deflection prism does not change the light path, the space of the system is not fully utilized and the miniaturization can not be continued, the invention uses the deflection prism to miniaturize the optical system.
(8) The invention adopts ocular to image and homogenize the light intensity, and obtains a high-quality measuring curve.
(9) The invention can control the diameter of the whole optical system within 14 mm.
(10) The probe is manufactured by adopting a compression molding process of a resin material, and the spherical surface, the aspherical surface and the plane are integrated into a whole at the same time, so that all optical devices of the optical system are miniaturized, and the optical machine size precision of the optical system is higher.
(11) The invention can coaxially assemble the optical devices, is arranged in a pen type, has more compact space utilization, and can be manufactured into a portable measuring pen; the various optical devices of the invention are made of resin materials and are formed by injection molding, thus improving the precision and repeatability of the devices and reducing the manufacturing cost. The portable low-cost pen-type measuring instrument is beneficial to mass civil popularization and can be a large data terminal.
Drawings
FIG. 1 is a diagram of an exemplary total reflection critical angle measurement system.
Fig. 2 is a schematic view of the structure of the probe body according to the present invention.
Fig. 3 is a schematic structural view of the present invention.
FIG. 4 is a graph showing the measurement of air (refractive index 1.0) according to the present invention.
FIG. 5 is a graph showing the measurement of pure water (refractive index 1.333) according to the present invention.
Fig. 6 is an image of the present invention when measuring medium refractive index liquid (n=1.38).
Fig. 7 is an image of the present invention when measuring a high refractive index liquid (n=1.429).
The device comprises an S1-light inlet surface, an S2-first reflecting surface, an S3-working surface, an S4-second reflecting surface, an S5-light outlet surface, an S6-first light inlet surface, an S7 second light inlet surface, a U1-light source, a U2-image sensor, a U3-prism, a U4-probe body, a U5-deflection prism, a U6-eyepiece, X-measured liquid and a C1-connecting pin.
Detailed Description
The present invention will be described in further detail with reference to examples, but embodiments of the present invention are not limited thereto.
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, based on the embodiments of the invention, which are apparent to those of ordinary skill in the art without inventive faculty, are intended to be within the scope of the invention. Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, based on the embodiments of the invention, which are apparent to those of ordinary skill in the art without inventive faculty, are intended to be within the scope of the invention.
In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.
Notably, are: in this application, where some technical means known or conventional technical means are required to be applied to the present application, there may be cases where the technical means which are known or/and conventional technical means are not specifically described herein, but the technical means cannot be specifically disclosed herein, and the present application is not considered to be in accordance with the twenty-sixth third clause of the patent law.
Example 1:
the invention designs an optical system with pen-type layout for measuring the refractive index of liquid and a measuring method thereof, integrates a probe, a light source, an image sensor and the like into a whole to form a miniaturized optical system, can be used for measuring the refractive index of liquid, adopts a probe designed by adopting a working mode that light beams are concentrated on a working surface, so that the effective area is very small and approximates to a point, thereby enabling the volume of the whole system to be designed smaller, and particularly adopts the following setting structure as shown in figures 2-3: comprising a light source U1 for generating a light beam, a probe body U4 for refracting an incident light beam, and an image sensor U2 for receiving an outgoing light image, the probe body U4 comprising
A light inlet surface S1 which allows the light beam generated by the light source U1 to enter and form light with a specific divergence angle (preferably-5 DEG to 5 DEG),
a first reflecting surface S2 for reflecting light generated by the light inlet surface S1 and having a specific divergence angle (preferably, -5 DEG to 5 DEG),
the light beams reflected by the first reflecting surface S2 are converged to form a working surface S3 of an effective area approximating a point, and when the working surface S3 contacts the measured liquid, light converged at different angles in the effective area is transmitted and/or totally reflected,
a second reflecting surface S4 for reflecting the light beam totally reflected by the working surface S3 again,
the light beam reflected by the second reflecting surface S4 is shaped and then emitted to an emitting surface S5 other than the probe body U4.
As a preferable arrangement, the optical system is used for realizing the measurement of the refractive index of the liquid, and comprises a light source U1 for generating a light beam, wherein an LED light source is adopted and can emit monochromatic light to form the light beam and irradiate the light beam into a probe body U4;
a probe body U4 for refracting incident light beams and an image sensor U2 for receiving outgoing light images, the probe body U4 comprising
The light inlet surface S1 is used for taking in the incident light in a certain included angle of the light source (LED) U1, the light inlet surface S1 is preferably in an aspheric structure and is coaxially arranged with the light source (LED) U1, the light inlet surface S1 is used for taking in the incident light in the certain included angle of the LED into the probe body U4 and forming emergent light with a specific angle (preferably-5 DEG), the emergent light is called emergent light 1, the total included angle of the emergent light 1 is related to the interval value of refractive index measurement, the larger the angle is, and the larger the interval value is, and the smaller the opposite is;
the first reflecting surface S2 preferably has a planar structure, and the outgoing light 1 is totally or specularly reflected by the first reflecting surface S2, so that the reflected light 1 is formed and projected onto the working surface S3. The inclination angle of the first reflecting surface S2 and the working surface S3 determines the central value of refractive index measurement, and different sections of refractive index can be measured by changing the inclination angle of the surface under the condition that other parts of the probe are not changed; under the condition of ensuring the unchanged precision, series products with different measuring ranges can be developed;
the working surface S3, the reflected light 1 is converged on the working surface S3, and a part of light is transmitted into the measured liquid X according to the refractive index of the measured liquid X, and the part of light is totally reflected on the second reflecting surface S4, and the part of light totally reflected becomes reflected light 2. The reduction of the effective area of the working surface S3 reduces the measurement volume of the sample, and the whole system can be greatly miniaturized;
the second reflecting surface S4 totally reflects or specularly reflects the reflected light 2 on the second reflecting surface S4, and projects the reflected light onto the exit surface S5, and this light becomes reflected light 3. The second reflecting surface S4 and the first reflecting surface S2 are preferably arranged with the same inclination angle, so as to ensure that the axes of the reflected light 3 and the outgoing light 1 are parallel;
the output surface S5 is preferably an optical aspherical surface, the optical axis of which is parallel to the probe axis, and the reflected light 3 is shaped (collimated) and the output light is referred to as output light 2.
Example 2:
the present embodiment is further optimized based on the foregoing embodiment, and the parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and in order to better implement the present invention, the following arrangement structure is specifically adopted: a deflection prism U5 is further disposed between the exit end of the exit surface S5 and the image sensor U2.
As a preferable arrangement, a deflection prism U5 is provided so that the optical axis of the light emitted from the probe body U4 can be moved to the central axis. The optical axis and the central axis of the light emitted from the deflection prism U5 are coincident, and the whole optical system can be miniaturized; the light beam emitted from the deflection prism U5 may form a spot by the image sensor U2.
Example 3:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: an eyepiece U6 is also provided between the deflection prism U5 and the image sensor U2.
As a preferred arrangement, the light beam emerging from the deflection prism U5 can be further homogenized with an eyepiece.
Example 4:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the eyepiece U6 is composed of two optical aspherical surfaces.
As a preferable arrangement, the eyepiece U6 is an optical aspherical eyepiece, imaging and light intensity homogenization processing are performed, and then light forms a light spot with uniform brightness on the image sensor U2.
Example 5:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the working surface S3 is converged at the center of the working surface S3 when the light beams are converged, and is converged at the center of the working surface S3 when the working surface S3 is converged when the light beams are arranged, namely, the axial center range area of the working surface S3.
Example 6:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the size of the converging light beam at the central part of the working surface S3 is 0-1 mm, namely, the light beam is converged in a circle with the size of 0-1 mm of the axis of the working surface S3, and the diameter is preferably 1mm.
Example 7:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the light beam reflected by the second reflecting surface S4 is parallel to the optical axis of the light beam emitted by the light inlet surface S1, namely the second reflecting surface S4 and the first reflecting surface S2 are set to be at the same inclination angle; the inclination angles of the second reflecting surface S4 and the first reflecting surface S2 are the same, so that the optical axis of the optical system is ensured to be parallel, and the manufacturing difficulty of the system is simplified. The second reflecting surface S4 may also be inclined at a different angle than the first reflecting surface S2, thus forming an off-axis optical system, which may reduce system components while increasing manufacturing difficulty.
Example 8:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the first reflecting surface S2 and the second reflecting surface S4 are arranged in mirror symmetry relative to the central line of the probe body U4; namely, the second reflecting surface S4 and the first reflecting surface S2 are set to the same inclination angle; the inclination angles of the second reflecting surface S4 and the first reflecting surface S2 are the same, so that the optical axis of the optical system is ensured to be parallel, and the manufacturing difficulty of the system is simplified. The second reflecting surface S4 may also be inclined at a different angle than the first reflecting surface S2, thus forming an off-axis optical system, which may reduce system components while increasing manufacturing difficulty.
Example 9:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the first reflecting surface S2 and the second reflecting surface S4 adopt a plane mirror of total reflection (total reflection principle) or specular reflection (metal or dielectric reflecting film).
Example 10:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the exit surface S5 is an optical aspheric lens.
Example 11:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the refractive index of the working surface S3 is 1.52-1.70, and the working surface S3 directly contacts with liquid, so that the requirement on the corrosion resistance of the resin material is high; according to the refractive index range of the measured liquid, the refractive index of the resin material is required to be between 1.52 and 1.70; different levels of optical material may be selected depending on the condition of the liquid being measured.
Example 12:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the incident surface S1 is an optical aspherical lens.
Example 13:
the present embodiment is further optimized based on any one of the foregoing embodiments, and the structural parts adopting the same technical structure as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further, in order to better implement the present invention, the following setting structure is specifically adopted: the probe body U4 is also provided with a connecting pin C1, and when the probe is arranged, the connecting pin C1 can be arranged at the light inlet surface S1 and the light outlet surface S5 of the probe body U4 so as to be convenient for connection with other follow-up components (deflection prism U5).
When the light emitting device is arranged, the emergent surface S5 can also be designed into an ocular lens (namely, a separate deflection prism U5 and an ocular lens U6 are not needed), and the light emitting device is directly imaged on the image sensor U2; it is also possible to shape only the reflected light 3 as input to the subsequent optical system.
Example 14:
a method for measuring an optical system of a pen-type layout for measuring refractive index of a liquid, as shown in fig. 2 and 3, comprises the steps of:
1) The light source U1 generates incident light, and the incident light forms a specific divergence angle (preferably-5 DEG) through the light inlet surface S1 and is projected to the first reflecting surface S2;
2) The first reflecting surface S2 performs total reflection or specular reflection, and reflects the reflected light to the working surface S3;
3) The working surface S3 converges the light reflected by the first reflecting surface S2, part of the converged light beam is transmitted out from the tested liquid X, and the rest light beams are totally reflected to the second reflecting surface S4;
4) The second reflecting surface S4 projects the light beam reflected by the working surface S3 to the emergent surface S5 in a total reflection or specular reflection mode;
5) The exit surface S5 transmits the light beam projected from the second reflection surface S4 to the image sensor U2.
Example 15:
the present embodiment is further optimized based on the foregoing embodiment, and the same technical structural parts as those adopted in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further in order to better implement the measurement method of the optical system for pen-type layout for measuring refractive index of liquid according to the present invention, before the light beam projected by the second reflecting surface S4 is transmitted to the image sensor U2 by the emitting surface S5, the optical axis of the light beam is further moved to the central axis by the deflection prism U5.
Example 16:
the present embodiment is further optimized based on the foregoing embodiment, and the structural parts adopting the same technology as those in the foregoing technical solution will not be described in detail in this technical solution, as shown in fig. 2 and fig. 3, and further in order to better implement the measurement method of the pen-type layout optical system for measuring refractive index of liquid according to the present invention, the light beam after passing through the deflecting prism U5 is further processed by imaging and homogenizing the light intensity through the eyepiece U6, and then is input to the image sensor U2.
As shown in fig. 3, when in use, monochromatic light (H, M, L from left to right) emitted by the LED light source U1 enters the light inlet surface (preferably an optical aspheric surface) S1 of the probe body U4 to deflect and form emergent light with a specific angle, and then total reflection or specular reflection occurs on the first reflecting surface S2 and is converged on the working surface S3, and the working surface S3 contacts the measured liquid X; when the refractive index of the measured liquid X is low concentration (lower than the critical value corresponding to the L rays), the L, M light ray and the H light ray are totally reflected on the working surface S3; when the refractive index of the measured liquid X is medium concentration, the L and M light rays are emitted into the liquid, and do not enter the internal optical system any more, and only the H light rays continue to be totally reflected; when the measured liquid is of high concentration (higher than the critical value corresponding to the H ray), both L, M and H rays are emitted into the measured liquid X.
The light totally reflected on the working surface S3 is continuously totally reflected or specularly reflected on the second reflecting surface S4, and then deflected on the exit surface S5 (preferably, an optical aspheric surface is adopted), and enters the deflecting prism U5 after exiting. Since the divergence angle of the light beam becomes small after passing through the exit surface S5, the light beam can pass through the deflection prism U5 having a limited size. The light emitted from the deflection prism U5 enters the eyepiece U6 for imaging and homogenizing the light intensity, and the light forms a light spot with uniform brightness on the image sensor U2 (preferably using a CMOS device).
As the refractive index of the measured liquid X increases, the spot reaching the image sensor U2 gradually fades from right to left, i.e. the cut-off moves from right to left. In practical application, the image sensor U2 (CMOS device) may convert an optical signal into a digital electrical signal, and the digital signal processing software may analyze the position of the falling edge of the digital signal curve, so as to calculate the refractive index of the measured liquid, which is not the disclosure of the technical scheme itself, so that the applicant only gives a technical idea (the technical idea can be implemented even by using the existing image processing technology) herein, and therefore, specific technical details are not repeated, but the disclosure of the technical scheme to be protected by the application cannot be considered insufficient due to the fact that the specific technical details are not disclosed, and the twenty-sixth third aspect of the patent law is not met.
The invention is characterized in that the system is miniaturized, the effective area of the working surface of the traditional refractometer is larger, the light of the light source is converged by the light inlet surface S1, and the light with different incidence angles required by design is obtained while the effective area of the working surface S3 is reduced. The former (light-entering surface S1) is the basis of miniaturization, and the latter (working surface S3) can effectively utilize the light energy of a surface light source LED (the conventional refractometer utilizes only the area of approximately one point of the LED center, whereas the present invention can utilize more than 50% of the area of the light-emitting surface of the LED).
The use of the deflection prism U5 enables the ocular lens U6 and the CMOS to be coaxial with the probe body U4, so that the manufacturing difficulty of an optical system is reduced, and the space layout is symmetrical. Since the deflecting prism U5 has a small size and is limited by the optical refractive index of its material, the light emitted from the probe body U4 needs to be collimated (divergence angle is reduced) by the emitting surface S5.
The light intensity distribution of the LED is more uneven due to the uneven light intensity distribution of the LED and the number of times the light is deflected and collimated by the exit surface S5. If the light intensity is not homogenized, the light intensity distribution on the image sensor U2 will fluctuate greatly, resulting in a plurality of equal-amplitude falling edges on the numerical signal curve, and software cannot identify the falling edge corresponding to the critical angle of total reflection, therefore, an eyepiece U6 for completing imaging and homogenizing light is arranged between the deflection prism U5 and the image sensor U2.
The light is diffused and the light intensity is homogenized by introducing the first light inlet surface S6 (preferably an optical aspheric surface) of the ocular lens U6, the parallel light at each working angle is focused and imaged by the first light outlet surface S7 (preferably an optical aspheric surface), and after the ocular lens U6 with the optical aspheric surface is adopted, the light intensity of an image point on the CMOS is uniform, and the uniformity can reach more than 80 percent.
When measuring air (refractive index 1.0), the digital signal curve is shown in fig. 4;
when pure water (refractive index 1.333) was measured, the digital signal curve is shown in fig. 5;
when medium refractive index liquid (n=1.38) is measured, the digital signal curve is shown in fig. 6;
when measuring a high refractive index liquid (n=1.429), the digital signal curve is shown in fig. 7;
as the refractive index increases, the curve falling edge gradually moves from right to left.
The foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and any simple modification, equivalent variation, etc. of the above embodiment according to the technical matter of the present invention fall within the scope of the present invention.
Claims (10)
1. An optical system for pen-type layout of refractive index measurement of a liquid, characterized in that: comprising a light source (U1) for generating a light beam, a probe body (U4) for refracting an incident light beam, and an image sensor (U2) for receiving an image of the emitted light, the probe body (U4) comprising
A light-entering surface (S1) which can enter the light beam generated by the light source (U1) and form an emergent light beam,
a first reflecting surface (S2) for reflecting the light beam emitted from the light inlet surface (S1),
the light beams reflected by the first reflecting surface (S2) are converged to form a working surface (S3) of an effective area which approximates a point, and when the working surface (S3) contacts the tested liquid, light converged at different angles in the effective area is transmitted and/or totally reflected,
a second reflecting surface (S4) for reflecting the light beam totally reflected by the working surface (S3),
the beam reflected by the second reflecting surface (S4) is shaped and then emitted to an emitting surface (S5) other than the probe body (U4).
2. The optical system for pen format for liquid refractive index measurement of claim 1, wherein: a deflection prism (U5) is also arranged between the emergent end of the emergent surface (S5) and the image sensor (U2).
3. The optical system for pen format for liquid refractive index measurement of claim 2, wherein: an eyepiece (U6) is also arranged between the deflection prism (U5) and the image sensor (U2).
4. An optical system for pen format for liquid refractive index measurement according to claim 3, characterized in that: the eyepiece (U6) is formed by two optical aspheres.
5. The optical system for pen layout for liquid refractive index measurement according to claim 1 or 2 or 3 or 4, wherein: the working surface (S3) is converged at the central part of the working surface (S3) when the light beams are converged.
6. The optical system for pen layout for liquid refractive index measurement according to claim 1 or 2 or 3 or 4, wherein: the light beam reflected by the second reflecting surface (S4) is parallel to the optical axis of the light beam emitted by the light inlet surface (S1).
7. The optical system for pen layout for liquid refractive index measurement according to claim 1 or 2 or 3 or 4, wherein: the first reflecting surface (S2) and the second reflecting surface (S4) are arranged in mirror symmetry relative to the central line of the probe body (U4).
8. The method for measuring an optical system for a pen-type layout for measuring refractive index of a liquid according to any one of claims 1 to 7, wherein: comprising the following steps:
1) The light source (U1) generates incident light and projects the incident light to the first reflecting surface (S2) through the light inlet surface (S1);
2) The first reflecting surface (S2) performs total reflection or specular reflection, and reflects the reflected light onto the working surface (S3);
3) The working surface (S3) converges the light reflected by the first reflecting surface (S2), part of the converged light beam is transmitted out of the tested liquid (X), and the rest light beam is totally reflected to the second reflecting surface (S4);
4) The second reflecting surface (S4) projects the light beam reflected by the working surface (S3) to the emergent surface (S5) through a total reflection or specular reflection mode;
5) The emission surface (S5) transmits the light beam projected by the second reflection surface (S4) to the image sensor (U2).
9. The measurement method of an optical system for pen layout for liquid refractive index measurement according to claim 8, wherein: the emergent surface (S5) also moves the optical axis of the light beam to the central axis through the deflection prism (U5) before transmitting the light beam projected by the second reflecting surface (S4) to the image sensor (U2).
10. The measurement method of an optical system for pen layout for liquid refractive index measurement according to claim 9, wherein: the light beam passing through the deflection prism (U5) is subjected to imaging and light intensity homogenization treatment through an ocular lens (U6), and then is input to an image sensor (U2).
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105954232A (en) * | 2016-05-26 | 2016-09-21 | 北京领航力嘉机电有限公司 | Liquid refractive index measuring system |
| CN109187431A (en) * | 2018-10-23 | 2019-01-11 | 北京博芮思商贸有限公司 | A kind of measuring device for liquid refractive index and measurement method |
| CN109187432A (en) * | 2018-10-23 | 2019-01-11 | 北京博芮思商贸有限公司 | A kind of measuring device for liquid refractive index and measurement method |
| CN110320179A (en) * | 2019-07-25 | 2019-10-11 | 四川维思达光学技术有限公司 | A kind of the liquid refractivity test probe and its anaclasis method of working face optically focused |
| CN110333187A (en) * | 2019-07-25 | 2019-10-15 | 四川维思达光学技术有限公司 | A kind of detection spoon measuring strength of fluid |
| CN211122528U (en) * | 2019-07-25 | 2020-07-28 | 四川维思达光学技术有限公司 | Pen-type layout optical system for measuring refractive index of liquid |
-
2019
- 2019-07-25 CN CN201910675821.8A patent/CN110398476B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105954232A (en) * | 2016-05-26 | 2016-09-21 | 北京领航力嘉机电有限公司 | Liquid refractive index measuring system |
| CN109187431A (en) * | 2018-10-23 | 2019-01-11 | 北京博芮思商贸有限公司 | A kind of measuring device for liquid refractive index and measurement method |
| CN109187432A (en) * | 2018-10-23 | 2019-01-11 | 北京博芮思商贸有限公司 | A kind of measuring device for liquid refractive index and measurement method |
| CN110320179A (en) * | 2019-07-25 | 2019-10-11 | 四川维思达光学技术有限公司 | A kind of the liquid refractivity test probe and its anaclasis method of working face optically focused |
| CN110333187A (en) * | 2019-07-25 | 2019-10-15 | 四川维思达光学技术有限公司 | A kind of detection spoon measuring strength of fluid |
| CN211122528U (en) * | 2019-07-25 | 2020-07-28 | 四川维思达光学技术有限公司 | Pen-type layout optical system for measuring refractive index of liquid |
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