Universal reflective optical sensor

Abstract

The utility model provides a universal reflective optical sensor, which relates to the technical field of optical sensors and comprises a shell, a light emitting unit, a coaxial receiving unit and a parallel receiving unit. A window is formed in one side of the shell, an optical filter is installed on the window, a light isolation plate perpendicular to the optical filter is arranged in the shell, and the interior of the shell is divided into a transmitting cavity and a receiving cavity by the light isolation plate. The light emitting unit is arranged in the emitting cavity and comprises a light source and an emitting lens. The coaxial receiving unit is arranged in the transmitting cavity and comprises a first detector and a spectroscope, and the spectroscope is arranged between the light source and the transmitting lens and used for focusing first reflected light reflected by the mirror surface of the object to be detected on the first detector. And the parallel receiving unit is arranged in the receiving cavity, comprises a second detector and a receiving lens, and is used for focusing second reflected light diffusely reflected by the object to be detected on the second detector. The device is high in accuracy when detecting the to-be-detected object reflected by the strong mirror, and is wide in application range.

Description

Technical Field

[0001] The utility model relates to the technical field of optical sensors, in particular to a general-purpose reflective optical sensor. Background Art

[0002] An optoelectronic switch refers to an optical sensor that uses a light source as a medium and applies the photoelectric effect. When the light source is blocked by an object or undergoes reflection, radiation, and light shielding, resulting in a change in the received light amount, it detects the presence, size, and brightness of an object and outputs a signal. Compared with the opposed-type optoelectronic switch, the reflective optoelectronic switch can integrate the transmitter and receiver into one body, making installation and debugging more convenient. However, the reflective optoelectronic switch has great limitations on the surface characteristics of the object to be measured. For example, in a diffuse reflection optoelectronic switch, the transmitter and receiver are generally arranged side by side. When detecting a strongly specularly reflecting object to be measured, the receiver cannot receive the signal light. Similarly, in a specular reflection optoelectronic switch, when detecting a strongly specularly reflecting object to be measured, false detection is likely to occur. Content of the Utility Model

[0003] The utility model aims to provide a general-purpose reflective optical sensor to solve the limitations of the reflective optoelectronic switch on the surface characteristics of the object to be measured in the prior art, improve the accuracy of the reflective optoelectronic switch when detecting a strongly specularly reflecting object to be measured, reduce the occurrence of false detection, and improve the versatility of the reflective optoelectronic switch.

[0004] To achieve the above object, the utility model provides a general-purpose reflective optical sensor, which includes a housing, a light emission unit, a coaxial receiving unit, and a side-by-side receiving unit.

[0005] A window is opened on one side of the housing, and a filter is installed on the window. A light-shielding plate perpendicular to the filter is arranged inside the housing, and the light-shielding plate divides the interior of the housing into an emission cavity and a receiving cavity.

[0006] The light emission unit is arranged in the emission cavity and includes a light source and an emission lens for emitting a detection beam.

[0007] The coaxial receiving unit is arranged in the emission cavity and includes a first detector and a beam splitter. The beam splitter is arranged between the light source and the emission lens; the emission lens and the beam splitter are used to cooperate to focus the first reflected light specularly reflected by the object to be measured on the first detector.

[0008] The side-by-side receiving unit is arranged in the receiving cavity and includes a second detector and a receiving lens; the receiving lens is used to focus the second reflected light diffusely reflected by the object to be measured on the second detector.

[0009] Further, when the object to be measured is a strongly specularly reflecting object to be measured, the tilt angle θ of the strongly specularly reflecting object to be measured satisfies:

[0010]

[0011] Among them, D is the central distance between the transmitting lens and the receiving lens, d is the exit width of the detection beam, L is the detection distance, and α is the divergence angle of the detection beam.

[0012] Furthermore, the divergence angle α of the detection beam satisfies:

[0013]

[0014] Among them, D is the central distance between the transmitting lens and the receiving lens, d is the exit width of the detection beam, L min is the minimum detection distance, and θ is the inclination angle of the strongly specularly reflecting object to be measured.

[0015] Furthermore, the included angle between the beam splitter and the optical axis of the detection beam is 60 degrees.

[0016] Furthermore, the transmittance of the beam splitter is higher than the reflectance.

[0017] Furthermore, the beam splitting ratio of the beam splitter is greater than or equal to 7:3.

[0018] Furthermore, the first detector is a photoelectric detection device with the ability to detect the light intensity distribution.

[0019] Furthermore, the first detector is selected from a photodiode array, a CCD, a CMOS, and a PSD.

[0020] Furthermore, it further includes a digital display screen, and the displayed value P of the digital display screen out is:

[0021]

[0022] Among them, P m is the energy received by the first detector, P d is the energy received by the second detector, and a and b are preset energy coefficients.

[0023] Furthermore, it further includes an alarm device, and the alarm device is used to give an alarm when the displayed value of the digital display screen is lower than the preset lower limit value or higher than the preset upper limit value.

[0024] The utility model has the following beneficial effects:

[0025] The general-purpose reflective optical sensor provided by the utility model has high accuracy when detecting a strongly specularly reflecting object to be measured, can reduce the occurrence of false detections, and has high versatility. Description of the Drawings

[0026] Figure 1 is the detection optical path diagram of the general-purpose reflective optical sensor in the embodiment of the utility model;

[0027] Figure 2 This is the optical path diagram for detecting a test object with strong specular reflection in the embodiment of the present utility model;

[0028] Figure 3 This is the optical path diagram when a detection blind area appears in the embodiment of the present utility model;

[0029] Figure 4 This is the schematic diagram of the detection beam and various parameters in the embodiment of the present utility model;

[0030] Figure 5 This is the optical path diagram of reflected stray light in the embodiment of the present utility model;

[0031] Figure 6 This is the optical path diagram when the test object with strong specular reflection is tilted in the embodiment of the present utility model;

[0032] Figure 7 This is the schematic diagram of the spot displacement on the first detector in the embodiment of the present utility model;

[0033] Figure 8 This is the comparison diagram of the response currents of two detectors in the embodiment of the present utility model;

[0034] Figure 9 This is the structural schematic diagram of the digital display screen in the embodiment of the present utility model.

[0035] Wherein, 1: housing; 2: light emitting unit; 3: coaxial receiving unit; 4: parallel receiving unit; 5: detection beam; 6: test object; 7: digital display screen; 8: anti-interference cover; 11: filter; 12: light baffle; 13: emission cavity; 14: receiving cavity; 21: light source; 22: emission lens; 31: first detector; 32: beam splitter; 41: second detector; 42: receiving lens; 51: first reflected light; 52: second reflected light; 53: reflected stray light; 61: test object with strong specular reflection; A: detection blind area. Specific embodiments

[0036] It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0037] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0038] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly. The connection can be a direct connection or an indirect connection.

[0039] In addition, in the present utility model, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0040] like Figure 1 The figure shows the detection optical path diagram of the universal reflective optical sensor in this embodiment. This embodiment provides a universal reflective optical sensor, which includes a housing 1 , a light emitting unit 2 , a coaxial receiving unit 3 and a parallel receiving unit 4 .

[0041] Among them, when a general object is irradiated by light, it can produce different degrees of specular reflection and diffuse reflection on the surface. By detecting the two reflected lights, it is possible to detect whether there is an object to be tested 6 in the monitoring area. In this embodiment, two receiving units are provided, wherein the coaxial receiving unit 3 is used to receive the specular reflected light coaxial with the emitted detection light beam 5, i.e., the first reflected light 51, and the parallel receiving unit 4 is used to receive the light diffusely reflected by the object to be tested 6, i.e., the second reflected light 52. The provision of two receiving units can reduce the problem of detection failure caused by the special surface of the object to be tested 6.

[0042] A window is provided on one side of the housing 1 , on which a filter 11 is installed. A light-isolating plate 12 perpendicular to the filter 11 is provided inside the housing 1 , and the light-isolating plate 12 separates the interior of the housing 1 into a transmitting cavity 13 and a receiving cavity 14 .

[0043] The housing 1 is in the shape of a box and can be installed on one side of the production line for detection, which is more convenient to install than the through-beam sensor. The side with the window is opposite to the production line, and the filter 11 can filter the ambient stray light to improve the accuracy of detection.

[0044] The light emitting unit 2 is disposed in the emitting cavity 13 , and includes a light source 21 and an emitting lens 22 , and is used to emit a detection light beam 5 .

[0045] Among them, the emission lens 22 is arranged close to the filter 11. After focusing the light rays emitted by the light source 21, a detection beam 5 is obtained. The detection beam 5 passes through the filter 11 and propagates towards the area to be measured on the production line. The divergence angle of the detection beam 5 can be controlled by the emission lens 22, and preferably, the emission angle can be set to be relatively small, so that the energy of the detection beam 5 is more concentrated, and the sensitivity of the detector is improved.

[0046] The coaxial receiving unit 3 is arranged in the emission cavity 13 and includes a first detector 31 and a beam splitter 32. The beam splitter 32 is arranged between the light source 21 and the emission lens 22. The emission lens 22 and the beam splitter 32 are used to cooperate to focus the first reflected light 51 specularly reflected by the object to be measured 6 on the first detector 31.

[0047] Among them, the coaxial receiving unit 3 is used to receive the first reflected light 51 reflected back from the surface of the object to be measured 6 along the emission direction of the detection beam 5. This part of the light rays is focused by the emission lens 22 and then irradiated onto the beam splitter 32, and further reflected by the beam splitter 32 onto the detection surface of the first detector 31, and the focus is set on the detection surface of the first detector 31.

[0048] The parallel receiving unit 4 is arranged in the receiving cavity 14 and includes a second detector 41 and a receiving lens 42. The receiving lens 42 is used to focus the second reflected light 52 diffusely reflected by the object to be measured 6 on the second detector 41.

[0049] Among them, when this embodiment is in use, the detection information of the first detector 31 and the second detector 41 can be integrated, so as to obtain a more accurate detection result, reduce the occurrence of false detections, and improve the applicable range of the general-purpose reflective optical sensor.

[0050] When this embodiment detects the diffusely reflecting object to be measured 6, the first reflected light 51 can return to the emission cavity 13 along the original optical path, and is focused on the detection surface of the first detector 31 through the emission lens 22 and the beam splitter 32 to obtain a first detection signal. The diffusely reflecting object to be measured 6 refers to the object to be measured 6 with a diffusely reflecting characteristic surface and can be detected by the diffuse reflection sensor. The second reflected light 52 enters the receiving cavity 14 and is focused on the detection surface of the second detector 41 through the receiving lens 42 to obtain a second detection signal. Through experiments, it is found that the first detection signal is stronger than the second detection signal. The general-purpose reflective optical sensor provided by this embodiment can process the first detection signal and the second detection signal by superposition or other means, so as to further improve the accuracy of the detection result.

[0051] Such as Figure 2As shown, this is the optical path diagram when the present embodiment detects a strong mirror-reflecting object to be tested. The detection light beam 5 irradiated on the surface of the strong mirror-reflecting object to be tested 61 mainly undergoes mirror reflection. At this time, the second reflected light 52 that the receiving lens 42 can receive is very small, and the energy received by the coaxial receiving unit 3 is extremely low, which is not enough to trigger the second detector 41 to respond. The first reflected light 51 is focused on the detection surface of the first detector 31 through the emitting lens 22 and the beam splitter 32. At this time, the light intensity energy received by the first detector 31 is strong enough to respond. Therefore, the universal reflective optical sensor provided in the present embodiment can detect the strong mirror-reflecting object to be tested 61 to prevent omissions in the monitoring area.

[0052] Existing reflective optical sensors have high requirements on the posture of the strong mirror reflection object 61 to be tested. When the strong mirror reflection object 61 to be tested is tilted, it is easy to fail to detect. The universal reflective optical sensor provided in this embodiment can tolerate the strong mirror reflection object 61 to be tested having a large inclination angle. When the coaxial receiving unit 3 cannot receive the returned light, the parallel receiving unit 4 can be used for detection. When the divergence angle of the detection light beam 5 is small, and the reflection surface of the strong mirror reflection object 61 to be tested is not perpendicular to the optical axis, the first reflected light 51 may not be able to return to the transmitting lens 22. At this time, the first detector 31 may not be able to obtain sufficient light intensity energy to respond, and it is necessary to use the parallel receiving unit 4 for supplementation. Therefore, it is necessary to limit the inclination angle of the strong mirror reflection object 61 to be tested and the divergence angle of the detection light beam 5 to improve the detection capability of this embodiment. The inclination angle θ is the deflection angle of the reflection surface of the strong mirror reflection object 61 to be tested, such as Figure 3 As shown, it is the optical path diagram when the detection blind spot appears in this embodiment. In this embodiment, the clockwise rotation of the object to be tested 6 is +θ, and the counterclockwise rotation is -θ. When the object to be tested 6 rotates along the -θ direction, the displacement of the first reflected light 51 on the emitting lens 22 exceeds d / 2 and cannot be received by the first detector 31. At the same time, in actual measurement, in most cases L>>d, so the inclination angle θ is preferably greater than 0. When the inclination angle θ is equal to 0, the strong mirror reflection object to be tested 61 does not deflect and can be measured directly. When the object to be tested 6 rotates along the +θ direction, as long as the second detector 41 can receive the first reflected light 51 from the object to be tested 6, detection can be performed normally, so a larger rotation angle can be provided.

[0053] In this embodiment, the tilt angle θ is the angle between the vertical line of the reflection surface of the strong specular reflection object 61 and the optical axis of the emission lens 22, and the tilt angle θ satisfies:

[0054]

[0055] Wherein, D is the central distance between the transmitting lens 22 and the receiving lens 42, d is the outgoing width of the detection beam 5, L is the detection distance, and α is the divergence angle of the detection beam 5.

[0056] In this embodiment, when detecting the strong specular reflection object 61 to be measured, it can tolerate a relatively large inclination angle of the object 6 to be measured, and the detection result can still maintain a high accuracy. The inclination angle of the object 6 to be measured can be limited according to the structure of the production line, such as setting side baffles, etc.

[0057] Furthermore, as Figure 3 shown, when the emission angle of the detection beam 5 is small, the first reflected light 51 may fall between the transmitting lens 22 and the receiving lens 42. At this time, neither the first detector 31 nor the second detector 41 can receive light with sufficient intensity and respond, so a detection blind area A will be generated. To eliminate the detection blind area A, it is necessary to limit the divergence angle of the detection beam 5.

[0058] As Figure 4 shown, it is a schematic diagram of the detection beam and various parameters in the embodiment. According to common sense, the closer the optical axis of the light is to the central axis of the lens, the better the focusing effect of the lens, that is, the focusing effect of the paraxial beam is better than that of the marginal beam. Whether there is light passing through the central axis of the transmitting lens 22 and the central axis of the receiving lens 42 can be used as the limit position for judgment. If there is no light passing through the above central axis, it is considered that the corresponding detector does not respond. Therefore, when the strong specular reflection object 61 to be measured is inclined, the light spot generated by the first reflected light 51 on the detector should at least cover half of the area of one of the lenses, so that at least one of the first detector 31 and the second detector 41 can receive light with sufficient intensity. The spot diameter of the first reflected light 51 is:

[0059] d 1 = 2L tanα(secθ + 1) + d

[0060] To meet the above requirements, it should be satisfied that d 1 > D. Considering that the spot size of the first reflected light 51 is the smallest during short-distance measurement, the minimum divergence angle of the detection beam 5 should be:

[0061]

[0062] Wherein, D is the central distance between the transmitting lens 22 and the receiving lens 42, d is the outgoing width of the detection beam 5, L min is the minimum detection distance, and θ is the inclination angle of the strong specular reflection object 61 to be measured.

[0063] This embodiment can eliminate the detection blind area by increasing the divergence angle of the detection beam 5, thereby further improving the detection accuracy. Moreover, when the divergence angle of the detection beam 5 is enlarged, the tolerance range for the tilt angle of the strongly specularly reflective object to be measured 61 can be greater, which can further improve the detection stability of this embodiment.

[0064] In this embodiment, the included angle between the beam splitter 32 and the optical axis of the detection beam 5 is 60 degrees.

[0065] As Figure 5 shown, it is a schematic optical path diagram of the reflected stray light in the emission cavity of this embodiment. Since the light source 21, the beam splitter 32, and the first detector 31 are arranged in the emission cavity 13 at the same time, the light source 21 and the beam splitter 32 will generate partial stray light, resulting in the first detector 31 being vulnerable to stray light interference inside the housing 1. Therefore, preferably, the beam splitter 32 is arranged at an included angle of 60 degrees with the optical axis of the detection beam 5. Such an arrangement can reduce the reflected stray light 53 reflected by the beam splitter 32 after the detection beam 5 emitted by the light source 21 is split by the beam splitter 32 from entering the first detector 31 through multiple reflections inside the housing 1, thereby reducing interference. Preferably, the light-blocking plate 12 is blackened and provided with anti-reflection patterns such as extinction patterns to reduce light reflection, and an anti-interference cover 8 is arranged around the first detector 31 to minimize the interference of stray light inside the housing 1 as much as possible.

[0066] In this embodiment, the first detector 31 is a photoelectric detection device with the ability to detect the light intensity distribution.

[0067] As Figure 6 shown, it is an optical path diagram when the strongly specularly reflective object to be measured is tilted in this embodiment. When the strongly specularly reflective object to be measured 61 has a tilt angle θ, there is a certain included angle between the first reflected light 51 and the central axis of the emission lens 22. Therefore, the light spot on the first detector 31 will have a certain displacement, as Figure 7 shown, it is a schematic diagram of the light spot displacement on the first detector in this embodiment. By comparing the light spot displacement on the first detector 31 at this time, it can be known whether the tilt posture of the object to be measured 6 in the monitoring area has changed at this time, and this is monitored. Preferably, the first detector 31 can use a photodiode array, CCD, CMOS, PSD, etc., which are photoelectric detectors with a certain ability to detect the light intensity distribution.

[0068] In this embodiment, the transmittance of the beam splitter 32 is higher than the reflectivity. Preferably, the splitting ratio of the beam splitter 32 is greater than or equal to 7:3.

[0069] As Figure 8As shown in the figure, it is a comparison diagram of the response currents of two detectors in this embodiment. The splitting ratio of the beam splitter 32 is 1:1. Since the optical axis of the first reflected light 51 is close to coaxial with the emission optical axis of the detection beam 5, and the light rays after specular reflection are more concentrated than those after diffuse reflection, the signal intensity that the first detector 31 can receive is much greater than that of the second detector 41. To increase the detection distance, in this embodiment, a beam splitter 32 with a transmittance higher than the reflectivity is used, so that the detection beam 5 emitted towards the detection area can have greater energy. Preferably, the splitting ratio of the beam splitter 32 can be selected as a beam splitter 32 with a light transmittance higher than the reflectivity such as 7:3, 8:2, etc., so that this embodiment can not only increase the detection distance, but also help reduce the stray light in the emission cavity 13 of the housing 1 and prevent interference with the first detector 31.

[0070] As Figure 9 shown, it is a schematic structural diagram of the digital display screen in this embodiment. This embodiment further includes a digital display screen 7, and the displayed value P of the digital display screen 7 out is:

[0071]

[0072] wherein, P m is the energy received by the first detector 31, P d is the energy received by the second detector 41, and a and b are preset energy coefficients.

[0073] The light reflection characteristics of the surfaces of different objects to be measured 6 are different. Generally, specular reflection and diffuse reflection exist simultaneously. This embodiment can simultaneously obtain the specularly emitted light and the diffusely reflected light on the surface of the object to be measured 6 through the first detector 31 and the second detector 41, thereby improving the accuracy of the detection result and expanding the applicable range of the general-purpose reflective optical sensor. Considering that the light intensities received by the first detector 31 and the second detector 41 are different, this embodiment corrects the display result, and the energy coefficients a and b can be obtained through experimental calibration. When measuring different objects to be measured 6, the energy coefficients a and b can be adjusted so that the output quantities of the first detector 31 and the second detector 41 are in the same order of magnitude, so as to maintain the measurement sensitivity to different objects to be measured 6. The energy that the first detector 31 and the second detector 41 can receive is related to the splitting ratio of the beam splitter 32, the distance between the emission optical path and the reception optical path, and is also related to the measurement range during the design of the sensor. Therefore, preferably, before measuring different objects to be measured 6, two energy coefficients a and b are obtained through calibration. Preferably, the display result of the digital display screen can also be the difference between the calibrated value and the actually measured value. The displayed value in this embodiment can be obtained by processing the output signals of the two detectors through a circuit or a control unit.

[0074] In this embodiment, an alarm device is further included. The alarm device is used to give an alarm when the display value of the digital display screen 7 is lower than the preset lower limit value or higher than the preset upper limit value.

[0075] Among them, through calibration, not only two coefficients a and b can be obtained, but also the range of the display value of the digital display screen 7 can be obtained. According to this range, the preset lower limit value and the preset upper limit value can be set. When the display value of the digital display screen 7 is within this range, it indicates that the detection is normal. The change of the display value of the digital display screen 7 within this range can reflect the change of the body posture of the object to be measured 6. When the display value of the digital display screen 7 is greater than the preset upper limit value or less than the preset lower limit value, it indicates that the detection is abnormal. The alarm device can give an alarm for the staff to conduct a check. The alarm device can include a buzzer, and the above alarm function is realized through the structure of the alarm circuit or the controller.

[0076] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A universal reflective optical sensor, characterized in that: It comprises a housing (1), a light emitting unit (2), a coaxial receiving unit (3) and a parallel receiving unit (4); A window is provided on one side of the housing (1), a filter (11) is mounted on the window, a light isolation plate (12) perpendicular to the filter (11) is provided inside the housing (1), and the light isolation plate (12) separates the interior of the housing (1) into a transmitting cavity (13) and a receiving cavity (14); The light emitting unit (2) is arranged in the emitting cavity (13), comprises a light source (21) and an emitting lens (22), and is used for emitting a detection light beam (5); The coaxial receiving unit (3) is arranged in the emitting cavity (13), and comprises a first detector (31) and a beam splitter (32), wherein the beam splitter (32) is arranged between the light source (21) and the emitting lens (22); the emitting lens (22) and the beam splitter (32) are used to cooperate to focus the first reflected light (51) reflected by the mirror surface of the object to be measured (6) onto the first detector (31); The parallel receiving unit (4) is arranged in the receiving cavity (14), and comprises a second detector (41) and a receiving lens (42); the receiving lens (42) is used to focus the second reflected light (52) diffusely reflected by the object to be measured (6) onto the second detector (41).

2. The universal reflective optical sensor according to claim 1, characterized in that: When the object to be tested (6) is a strong specular reflection object to be tested (61), the inclination angle θ of the strong specular reflection object to be tested (61) satisfies: Wherein, D is the center distance between the transmitting lens (22) and the receiving lens (42), d is the emission width of the detection light beam (5), L is the detection distance, and α is the divergence angle of the detection light beam (5).

3. The universal reflective optical sensor according to claim 2, characterized in that: The divergence angle α of the detection light beam (5) satisfies: Wherein, D is the center distance between the transmitting lens (22) and the receiving lens (42), d is the emission width of the detection light beam (5), L min is the minimum detection distance, and θ is the tilt angle of the strong specular reflection object (61) to be detected.

4. The universal reflective optical sensor according to claim 1, characterized in that: The included angle between the beam splitter (32) and the optical axis of the detection light beam (5) is 60 degrees.

5. The universal reflective optical sensor according to claim 4, characterized in that: The transmittance of the beam splitter (32) is higher than its reflectance.

6. The universal reflective optical sensor according to claim 5, characterized in that: The beam splitter (32) has a beam splitting ratio greater than or equal to 7:

3.

7. The universal reflective optical sensor according to claim 1, characterized in that: The first detector (31) is a photoelectric detection device capable of detecting light intensity distribution.

8. The universal reflective optical sensor according to claim 7, characterized in that: The first detector (31) is selected from a photodiode array, CCD, CMOS, PSD.

9. The universal reflective optical sensor according to claim 1, characterized in that: It also includes a digital display screen (7), wherein the display value P of the digital display screen (7) is out for: Among them, P m is the energy received by the first detector (31), P d is the energy received by the second detector (41), and a and b are preset energy coefficients.

10. The universal reflective optical sensor according to claim 9, characterized in that: It also comprises an alarm device, which is used to give an alarm when the display value of the digital display screen (7) is lower than a preset lower limit value or higher than a preset upper limit value.

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