Laser position sensor

Abstract

The utility model relates to a laser position sensor, which belongs to the technical field of sensors and comprises a light source emitting end, a light source receiving end and a light source transmitting end, the attenuation reflecting mirror is used for receiving laser beams emitted by the laser light source and attenuating laser energy according to a certain proportion; the collimating lens receives the signal sent by the attenuation reflector and sends out the signal in parallel; and the light source receiving and processing end comprises a narrow-band filter lens and a linear array CMOS image photosensitive device, and the narrow-band filter lens receives the parallel light emitted by the collimating lens, filters the parallel light and sends the filtered parallel light to the linear array CMOS image photosensitive device for imaging. The device is good in linearity and high in precision, is not liable to be affected by environmental factors to generate measurement errors, and can meet the requirements of long-distance installation and measurement.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a laser position sensor. Background Art

[0002] The infrared sensors and ultrasonic sensors currently on the market use infrared light and ultrasonic waves as the media for signal detection, respectively. These two signals have strong divergence, limited transmission distances, and poor linearity, and cannot meet the needs of high-precision and long-distance measurements. In addition, due to their special material properties, their signal accuracy and measurement results are greatly affected by temperature.

[0003] With the continuous development of science and technology, the industrial production field has higher and higher requirements for high-precision position measurement, width measurement, and object size measurement, which has promoted the leapfrog development of sensor technology. At present, the sensors used for edge detection, outer diameter measurement and width measurement on the market mainly include infrared sensors, ultrasonic sensors, visual sensors (industrial cameras), etc. Infrared and ultrasonic sensors are relatively cheap, but they have the following shortcomings: First, they are the first choice for users in occasions where the detection accuracy requirements are not high and the cost control is strict. Due to their low accuracy, they are easily affected by environmental factors (such as temperature, humidity, dust, etc.), and cannot meet the high-precision measurement field; second, ultrasonic and infrared are used as sensor detection media, with strong divergence and low linearity, and cannot achieve high-precision and long-distance measurement; third, the components and structures of ultrasonic sensors and infrared sensors are greatly affected by temperature, resulting in large errors. Utility Model Content

[0004] To this end, the technical problem to be solved by the utility model is to overcome the deficiencies in the prior art and provide a laser position sensor with good linearity, high precision, not easily affected by environmental factors to produce measurement errors, and capable of long-distance installation and achieving high-precision measurement requirements.

[0005] In order to solve the above technical problems, the utility model provides a laser position sensor, which includes:

[0006] The light source transmitting end includes a laser light source, an attenuation reflector and a collimating lens. The laser light source is used to generate a light source; the attenuation reflector is used to receive a laser beam emitted by the laser light source and attenuate the laser energy in a certain proportion; the collimating lens receives a signal emitted by the attenuation reflector and transmits the signal in parallel;

[0007] The light source receiving and processing end includes a narrow-band filter and a linear array CMOS image sensing device. The narrow-band filter receives the parallel light emitted by the collimating lens, and filters the parallel light and sends it to the linear array CMOS image sensing device for imaging.

[0008] In an embodiment of the present utility model, the light source transmitting end and the light source receiving and processing end are both arranged in a shell, and the shell is a U-shaped structure.

[0009] In one embodiment of the present invention, the narrowband filter is a narrowband filter with a passband width of 635 nm.

[0010] In one embodiment of the present invention, an image gain adaptive adjustment module is also included, which is used to automatically adjust the image gain according to the light transmittance of the material.

[0011] In one embodiment of the utility model, the image gain adaptive adjustment module includes a contrast detection unit, a microprocessor, an automatic gain adjustment unit and a storage device. The contrast detection unit receives the output signal of the linear array CMOS image photosensitive device, and sends its output contrast detection data to the automatic gain adjustment unit and the microprocessor. The automatic gain adjustment unit is electrically connected to the linear array CMOS image photosensitive device and is used to adjust the image gain of the linear array CMOS image photosensitive device; the microprocessor analyzes and processes the data and sends the results to the storage device for storage.

[0012] In one embodiment of the present invention, a display unit is further included. The display unit is connected to the output end of the microprocessor and is used to display real-time detection position data.

[0013] In one embodiment of the present invention, the display unit is a digital tube.

[0014] In one embodiment of the present invention, an output unit is further included, and the output unit is connected to the output terminal of the microprocessor.

[0015] In one embodiment of the present invention, the output unit is 0-10MA / 4-20ma current output or 485 communication output.

[0016] In one embodiment of the utility model, an operation button is further included, which is connected to the microprocessor and is used for parameter setting and calibration of the laser position sensor.

[0017] The above technical solution of the utility model has the following beneficial effects compared with the prior art:

[0018] The laser position sensor described in the utility model can be used for edge detection, high-precision measurement of outer diameter and width of objects. The laser light source at the light source transmitting end has the characteristic of high linearity. The light source is constrained to be a parallel light source infinitely close to the ideal state through a collimating lens to solve the divergence problem, thereby achieving high-precision and long-distance measurement. The receiving end adopts a linear array CMOS image photosensitive device to receive the light beam, and determines the position by judging the number of light beams transmitted or blocked. Since the linear array CMOS image photosensitive device has very high linearity and resolution, compared with infrared light sources or ultrasonic generators, it has the characteristics of good linearity, high precision, and is not easily affected by environmental factors. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein

[0020] Figure 1 It is a schematic diagram of the structure of the laser position sensor in the preferred embodiment of the utility model;

[0021] Figure 2 yes Figure 1 The schematic diagram of the structure of the light source emitting end of the laser position sensor shown;

[0022] Figure 3 yes Figure 1 The structural schematic diagram of the image gain adaptive adjustment module of the laser position sensor shown;

[0023] Explanation of the reference numerals in the specification: 1. light source transmitting end; 11. laser light source; 12. attenuation reflector; 2. light source receiving and processing end; 21. narrow-band filter; 22. linear array CMOS image sensing device; 13. collimating lens; 3. image gain adaptive adjustment module; 31. contrast detection unit; 32. microprocessor; 33. automatic gain adjustment unit; 34. storage; 35. display unit; 36. output unit; 37. operation button; 100. housing. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0025] Reference Figure 1 As shown, a laser position sensor described in the utility model includes:

[0026] The light source transmitting end 1 comprises a laser light source 11, an attenuation reflector 12 and a collimating lens 13. The laser light source 11 is used to generate a light source; the attenuation reflector 12 is used to receive the laser beam emitted by the laser light source 11 and attenuate the laser energy according to a certain ratio; the collimating lens 13 receives the signal emitted by the attenuation reflector 12 and transmits the signal in parallel; since the light source transmitting end 1 uses a high-precision laser light source 11 and a collimating lens 13 composed of a convex lens and a concave lens, the light source passing through the collimating lens 13 reaches parallel light close to an ideal state, thus solving the problem of divergence of the light source;

[0027] The light source receiving and processing end 2 includes a narrowband filter 21 and a linear array CMOS image sensing device 22. The narrowband filter 21 receives the parallel light emitted by the collimating lens 13, and filters the parallel light and sends it to the linear array CMOS image sensing device 22 for imaging.

[0028] When working, the laser light source 11 is used as the signal generating light source, and the laser beam is irradiated to the attenuation reflector 12 at a certain angle, and the laser beam is converted into a nearly parallel beam through the attenuation reflector 12 and the collimating lens 13. The attenuation reflector 12 uses a coated lens to attenuate the laser energy at a certain ratio to prevent the laser energy from being too high, causing damage to the linear array CMOS image photosensitive device 22 of the light source receiving and processing end 2. Since the light source transmitting end 1 uses a high-precision laser light source 11 and a collimating lens 13 composed of a convex lens and a concave lens, the light source passing through the collimating lens 13 reaches a parallel light close to the ideal state, solving the problem of the divergence of the light source.

[0029] In this embodiment, the light source transmitting end 1 and the light source receiving and processing end 2 are both arranged in a housing 100, and the housing 100 is a U-shaped structure. Figure 3 shown.

[0030] Preferably, the narrowband filter 21 is a narrowband filter with a passband bandwidth of 635nm. When the parallel light emitted by the collimating lens 13 passes through the 635nm narrowband filter and irradiates the linear array CMOS image sensor 22, when an object is within the range of the parallel light beam, the light beam blocked by the object will not reach or partially reach the light source receiving and processing end 2, and then form an image on the linear array CMOS sensor. Since the linear array CMOS sensor is composed of a number of pixels, if there is a large contrast change between two adjacent pixels, it means that the pixel position is at the edge of the object, and the object position is determined in this way.

[0031] Furthermore, the present invention also includes an image gain adaptive adjustment module 3. When detecting different materials, due to the different transmittances of the materials, the quality of imaging on the linear array CMOS image sensing device 22 is also different. Through the image gain adaptive adjustment module 3, the image gain can be automatically adjusted according to the transmittance of the material, and thus the reflective material and the translucent material can also be stably detected.

[0032] like Figure 2 As shown, the image gain adaptive adjustment module 3 includes a contrast detection unit 31, a microprocessor 32, an automatic gain adjustment unit 33 and a storage 34. The contrast detection unit 31 is used to receive the output signal of the linear array CMOS image photosensitive device 22, and send its output contrast detection data to the automatic gain adjustment unit 33 and the microprocessor 32. The automatic gain adjustment unit 33 is electrically connected to the linear array CMOS image photosensitive device 22, and is used to adjust the image gain of the linear array CMOS image photosensitive device 22; the microprocessor 32 analyzes and processes the data, and sends the result to the storage 34 for storage. The laser position sensor achieves 0.01% error control by means of the optical properties of the laser and CMOS technology.

[0033] This embodiment further includes a display unit 35 , which is connected to the output end of the microprocessor 32 and is used to display real-time detection position data.

[0034] Preferably, the display unit 35 is a digital tube, which can display real-time detection position data.

[0035] The device further comprises an output unit 36, which is connected to the output terminal of the microprocessor 32. The output unit 36 ​​is a 0-10MA / 4-20ma current output or a 485 communication output.

[0036] Furthermore, it also includes an operation button 37 connected to the microprocessor 32 for parameter setting and calibration of the laser position sensor.

[0037] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention of the utility model.

Claims

1. A laser position sensor, characterized in that: include: A light source emitting end, comprising a laser light source, an attenuation reflector and a collimating lens, wherein the laser light source is used to generate a light source; The attenuation reflector is used to receive the laser beam emitted by the laser light source and attenuate the laser energy at a certain ratio; the collimating lens receives the signal emitted by the attenuation reflector and emits the signal in parallel; The light source receiving and processing end includes a narrow-band filter and a linear array CMOS image sensing device. The narrow-band filter receives the parallel light emitted by the collimating lens, and filters the parallel light and sends it to the linear array CMOS image sensing device for imaging.

2. A laser position sensor according to claim 1, characterized in that: The light source transmitting end and the light source receiving and processing end are both arranged in a shell, and the shell is a U-shaped structure.

3. A laser position sensor according to claim 1, characterized in that: The narrowband filter is a 635nm narrowband filter.

4. A laser position sensor according to claim 1, characterized in that: It also includes an image gain adaptive adjustment module for automatically adjusting the image gain according to the light transmittance of the material.

5. A laser position sensor according to claim 4, characterized in that: The image gain adaptive adjustment module includes a contrast detection unit, a microprocessor, an automatic gain adjustment unit and a storage device. The contrast detection unit is used to receive the output signal of the linear array CMOS image photosensitive device and send its output contrast detection data to the automatic gain adjustment unit and the microprocessor. The automatic gain adjustment unit is electrically connected to the linear array CMOS image photosensitive device and is used to adjust the image gain of the linear array CMOS image photosensitive device; the microprocessor analyzes and processes the data and sends the results to the storage device for storage.

6. A laser position sensor according to claim 5, characterized in that: It also includes a display unit, which is connected to the output end of the microprocessor and is used to display real-time detection position data.

7. A laser position sensor according to claim 6, characterized in that: The display unit is a digital tube.

8. The laser position sensor according to claim 5, characterized in that: It also includes an output unit, which is connected to the output terminal of the microprocessor.

9. A laser position sensor according to claim 8, characterized in that: The output unit is 0-10MA / 4-20mA current output or 485 communication output.

10. The laser position sensor according to claim 5, characterized in that: It also includes an operation button connected to the microprocessor.

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