CN213985377U

CN213985377U - Micro laser power thermopile sensor and laser power meter

Info

Publication number: CN213985377U
Application number: CN202023212741.6U
Authority: CN
Inventors: 潘吴达
Original assignee: Wenzhou Newborn Technology Co ltd
Current assignee: Wenzhou Newborn Technology Co ltd
Priority date: 2020-12-28
Filing date: 2020-12-28
Publication date: 2021-08-17
Anticipated expiration: 2030-12-28

Abstract

The utility model discloses a micro laser power thermopile sensor and a laser power meter, which comprises an aluminum alloy matrix, a low thermal conductivity coefficient film, a copper plating layer, an insulating layer, a thermopile sensitive layer, an absorber and a copper pressing ring; the aluminum alloy substrate is of a circular ring step structure, the low-thermal-conductivity-coefficient film and the aluminum alloy substrate form a concentric circle, the copper coating is arranged on the upper portion of the low-thermal-conductivity-coefficient film, the insulating layer is arranged on the upper portion of the copper coating in a wafer shape, the thermopile sensitive layer is arranged on the upper portion of the insulating layer, the absorber is arranged in the middle of the thermopile sensitive layer, and the copper pressing ring is arranged on the upper portion of the insulating layer; the film pressing ring structure adopted in the utility model reduces the processing difficulty; meanwhile, as the thin film material with low heat conductivity coefficient is adopted, most heat is concentrated on the thermopile sensitive layer, and the temperature difference between the cold end and the hot end of the thermopile is improved, so that the output voltage signal is increased, and the sensitivity of the sensor in measuring the micro power is improved.

Description

Micro laser power thermopile sensor and laser power meter

Technical Field

The utility model relates to a laser power measures technical field, specifically indicates a small laser power thermopile sensor and laser power meter.

Background

With the large number of applications of lasers, it is important to accurately measure laser power in either industrial, medical, communication, or military applications.

In the prior art, a laser power meter is generally used for measuring the power of the laser. Laser power meters are typically constructed with a built-in transducer power probe and display assembly. The sensors may be classified into photoelectric type sensors and thermoelectric type sensors according to principles. The principle of the photoelectric sensor is to directly convert light energy into a current or voltage signal through a photodiode so as to represent the magnitude of laser power. Although the photoelectric sensor has a shorter response time and a higher response frequency, the applicable wavelength of the photoelectric sensor is limited. The pyroelectric sensor generally uses a symmetrical thermopile to measure the temperature gradient formed in the substrate by the laser energy absorbed by the absorber, and output an electrical signal. The response time of the thermoelectric probe is relatively long, but the spectral measurement range is wide, and the thermoelectric probe can be used in ultraviolet to far infrared wave bands, so that the thermoelectric probe is more widely applied.

The existing thermopile sensor generally comprises an aluminum alloy matrix, an absorber, an insulating layer, a sensitive layer and a binding post, wherein the sensitive layer of the thermopile is positioned on the back of the absorber. When the existing thermoelectric sensor is applied to micro power measurement, in order to improve response and output voltage, an aluminum alloy substrate of an absorber part in the middle of the substrate needs to be processed to be 0.3 mm or even thinner, in order to accurately measure, the whole size error of the middle part needs to be controlled in a very small range, and the processing difficulty is high. And the middle part is made of aluminum alloy, so that the temperature gradient generated by the micro-power laser energy is very small, and a large electric signal is difficult to output. Therefore, when measuring small power, the signal needs to be amplified by a very large factor and is easy to distort, and the measurement accuracy is affected.

Therefore, a micro laser power thermopile sensor is a problem to be solved urgently.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is that among the prior art when the thermopile sensor processing degree of difficulty is big, output voltage signal is little, measure small power, technical problem that measurement accuracy is low.

In order to solve the technical problem, the utility model provides a technical scheme does: a micro laser power thermopile sensor and a laser power meter comprise an aluminum alloy substrate, a low-thermal-conductivity-coefficient film, a copper coating, an insulating layer, a thermopile sensitive layer, an absorber and a copper pressing ring;

the aluminum alloy substrate is of a circular ring step structure and comprises a first step and a second step, the outer diameters of the first step and the second step are the same, and the inner diameter of the second step is larger than that of the first step; the low coefficient of thermal conductivity film is disk form and diameter slightly is less than the second step internal diameter, the low coefficient of thermal conductivity film is placed and is become the concentric circles with the aluminum alloy base member on first step, the copper plating layer outer lane is the ring form, and the center is the disk form, and central disk diameter slightly is greater than the absorber diameter, the copper plating layer sets up in low coefficient of thermal conductivity film upper portion, the insulating layer is the disk form and sets up in copper plating layer upper portion, the sensitive layer of thermopile sets up in insulating layer upper portion, the sensitive layer both ends of thermopile are located copper plating layer outer lane and interior round position, the insulating layer top, the sensitive layer middle part of thermopile is located to the absorber, the copper clamping ring sets up in insulating layer upper portion, the copper clamping ring internal diameter is greater than the sensitive layer external diameter, copper clamping ring and sensitive layer contactless, the copper clamping ring adopts interference fit with the aluminum alloy base member.

Furthermore, the thermopile sensitive layer comprises a thermopile positive layer and a thermopile negative layer, and the thermopile negative layer and the thermopile positive layer are mutually symmetrical and closely connected.

Furthermore, a pure silver sheet is arranged on the thermopile sensitive layer, a binding post penetrating through the aluminum alloy matrix is arranged on the lower portion of one end of the pure silver sheet, and the binding post comprises an insulating base and a copper needle penetrating through the insulating base.

Furthermore, the copper plating layer and the low-thermal conductivity film are provided with first through holes matched with the insulating base.

Further, the insulating seat is a polytetrafluoroethylene insulating seat.

Furthermore, the low-thermal conductivity film is made of a nylon material.

A laser power meter with a built-in thermopile sensor of any one of claims 1-6, comprising an aluminum alloy front cover, an aluminum alloy main body, the thermopile sensor and an aluminum alloy rear cover, wherein the aluminum alloy main body is arranged on the upper portion of the aluminum alloy rear cover, a round sinking platform is arranged on the upper portion of the aluminum alloy main body, the thermopile sensor is arranged inside the round sinking platform, a second through hole penetrating through the aluminum alloy main body is arranged in the middle of the aluminum alloy main body, and a light through hole penetrating through the aluminum alloy front cover is arranged on the upper portion and in the middle of the aluminum alloy main body.

Further, cover behind aluminum alloy protecgulum and the aluminum alloy and all be equipped with a plurality of third through-holes that run through self, be equipped with the screw hole that corresponds with third through-hole position in the aluminum alloy main part, threaded hole is equipped with countersunk screw, countersunk screw is fixed as a whole with aluminum alloy protecgulum, aluminum alloy main part, thermopile sensor and aluminum alloy back cover.

Furthermore, be equipped with the jackscrew pad on the aluminum alloy main part, with the M4 hexagon socket head cap that the jackscrew pad cooperation was used and set up the shielded wire in aluminum alloy main part one side.

Compared with the prior art, the utility model the advantage lie in: the film pressing ring structure adopted in the utility model reduces the processing difficulty; meanwhile, as the thin film material with low heat conductivity coefficient is adopted, most heat is concentrated on the thermopile sensitive layer, and the temperature difference between the cold end and the hot end of the thermopile is improved, so that the output voltage signal is increased, and the sensitivity of the sensor in measuring the micro power is improved.

Drawings

Fig. 1 is a schematic structural diagram of a micro laser power thermopile sensor of the present invention.

Fig. 2 is a partial enlarged view of a micro laser power thermopile sensor according to the present invention.

Fig. 3 is a cross-sectional view of a micro laser power thermopile sensor of the present invention.

Fig. 4 is a schematic structural diagram of a laser power meter with a built-in thermopile sensor according to the present invention.

Fig. 5 is a schematic diagram of a fixing structure of a shielding wire of a laser power meter with a built-in thermopile sensor according to the present invention.

As shown in the figure: 1. the high-temperature-resistant and high-temperature-resistant thermopile comprises an aluminum alloy substrate, 2, a low-thermal-conductivity-coefficient film, 3, a copper plating layer, 4, an insulating layer, 5, a thermopile sensitive layer, 6, an absorber, 7, a copper pressing ring, 8, a first step, 9, a second step, 10, a thermopile positive electrode layer, 11, a thermopile negative electrode layer, 12, a pure silver sheet, 13, an insulating seat, 14, a copper pin, 15, a first through hole, 16, an aluminum alloy front cover, 17, an aluminum alloy main body, 18, a thermopile sensor, 19, an aluminum alloy rear cover, 20, a circular sinking platform, 21, a second through hole, 22, a light through hole, 23, a third through hole, 24, a threaded hole, 25, a sunk screw, 26, a shielding wire, 27, a jackscrew pad, 28, M4 inner hexagonal jackscrew, 29 and a binding post.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.

With the attached drawings 1-4, the working principle of the utility model is as follows:

the base body is made of aluminum alloy, the middle of the base body is supported by a low-heat-conductivity-coefficient film 2 (such as nylon 66), and the base body is fixed in the aluminum base body through interference fit of a copper pressing ring 7. When the power is measured slightly, the aluminum foil film can be replaced by the aluminum foil film which is made of the same structure. The middle part and the outer ring of the nylon film are plated with copper layers by adopting a vacuum coating process, the surface uniformity of the absorber 6 can be improved by the middle copper plating layer 3, errors caused by the deviation of light spots from the center are reduced, the absorber 6 is sprayed on the middle copper plating layer 3 by a plasma spraying process, and the diameter of the absorber is slightly smaller than that of the middle copper plating layer 3. The outer ring copper plating layer 3 is closely contacted with the copper pressing ring 7 to play a role in heat transfer. The insulating layer 4 serves to insulate and improve the bonding force of the thermopile sensing layer 5. The thermopile sensitive layer 5 is arranged on the insulating layer 4 and on the same side as the absorber 6. The cold end and the hot end of the device are respectively positioned at the outer ring copper plating layer 3 and the inner ring copper plating layer 3, and the middle supporting part adopts the nylon film with low heat conductivity coefficient, so that the heat generated by the laser energy absorbed by the absorber 6 can be conducted only through the thermocouple self forming the thermopile, a larger voltage signal than the existing design can be generated, and the measurement of the micro power is more accurate. The thermopile sensitive layer 5 and the binding post 29 are connected through the pure silver sheet 12 and the conductive silver adhesive. The pure silver sheet 12 is positioned on the same side of the sensitive layer, and a notch is arranged on the copper pressing ring 7, so that the pure silver sheet 12 can be connected with the bottom of the copper pin 14 in the binding post 29. The top of the copper pin 14 is arranged on the back of the substrate and is connected with a high-temperature-resistant lead to output a voltage signal.

The aluminum alloy front cover 16 is installed on the aluminum alloy main body 17 through a countersunk screw 25, the thermopile sensor 18 is pressed on a circular sinking platform 20 inside the main body by the front cover, the rear cover is also installed on the main body through the countersunk screw 25, and a binding post 29 and an output shielding wire 26 are connected through a high-temperature resistant lead. By replacing different cooling parts, such as a radiating fin with a larger size, cooling by a fan and water cooling, the power meter with different maximum measuring powers is manufactured. According to different use scenes, a signal conditioning circuit can be arranged in the device. The signal conditioning circuit includes: the device comprises an ultra-low noise power supply, a preceding stage instrument amplifier, an active low-pass filter, a double-T wave trap, a main amplifier, a voltage follower and a calibration circuit.

The precise power supply provides positive and negative power supplies required by the signal conditioning circuit. The pre-stage instrument amplifier amplifies the micro electric signal output by the sensor in low times, and the amplification factor is determined by the fixed precise resistor, so that the error caused by the change of the internal resistance of the sensor due to the temperature change of the substrate of the sensor is avoided. The active low-pass filter and the double-T wave trap can effectively filter high-frequency interference and 50Hz power frequency interference. The main amplifier amplifies the filtered signal, and outputs the amplified signal through the follower and the calibration circuit.

The present invention will be described in detail with reference to the accompanying drawings 1-5.

A micro laser power thermopile sensor comprises an aluminum alloy substrate 1, a low-thermal-conductivity-coefficient film 2, a copper plating layer 3, an insulating layer 4, a thermopile sensitive layer 5, an absorber 6 and a copper pressing ring 7;

the aluminum alloy substrate 1 is of a circular ring step structure, the aluminum alloy substrate 1 comprises a first step 8 and a second step 9, the outer side diameters of the first step 8 and the second step 9 are the same, and the inner diameter of the second step 9 is larger than that of the first step 8; the low-thermal-conductivity-coefficient film 2 is in a disc shape, the diameter of the low-thermal-conductivity-coefficient film 2 is slightly smaller than the inner diameter of the second step 9, the low-thermal-conductivity-coefficient film 2 is placed on the first step 8 and forms a concentric circle with the aluminum alloy matrix 1, the outer ring of the copper plating layer 3 is circular, the center is in a shape of a circular sheet, the diameter of the central circular sheet is slightly larger than that of the absorber 6, the copper plating layer 3 is arranged on the upper part of the low-heat-conductivity-coefficient film 2, the insulating layer 4 is arranged on the upper part of the copper plating layer 3 in a disc shape, the thermopile sensitive layer 5 is arranged on the upper part of the insulating layer 4, two ends of the thermopile sensitive layer 5 are positioned at the outer ring and the inner ring of the copper plating layer 3 and above the insulating layer 4, the absorber 6 is arranged in the middle of the thermopile sensitive layer 5, the copper pressing ring 7 is arranged on the upper part of the insulating layer 4, the inner diameter of the copper pressing ring 7 is larger than the outer diameter of the sensitive layer, the copper pressing ring 7 is not in contact with the sensitive layer, and the copper pressing ring 7 is in interference fit with the aluminum alloy matrix 1.

The thermopile sensitive layer 5 comprises a thermopile positive layer 10 and a thermopile negative layer 11, and the thermopile negative layer 11 and the thermopile positive layer 10 are mutually symmetrical and closely connected.

The thermopile sensitive layer 5 is provided with a pure silver sheet 12, the lower part of one end of the pure silver sheet 12 is provided with a binding post 29 penetrating through the aluminum alloy matrix 1, and the binding post 29 comprises an insulating base 13 and a copper needle 14 penetrating through the insulating base 13.

And the copper plating layer 3 and the low-heat-conductivity-coefficient film 2 are provided with first through holes 15 matched with the insulating base 13.

The insulating seat 13 is a polytetrafluoroethylene insulating seat 13.

The low-heat-conductivity-coefficient film 2 is made of a nylon material.

A laser power meter with a built-in thermopile sensor comprises an aluminum alloy front cover 16, an aluminum alloy main body 17, a thermopile sensor 18 and an aluminum alloy rear cover 19, wherein the thermopile sensor 18 is any one of the small laser power thermopile sensors 18; the aluminum alloy main part 17 sets up in 19 upper portions of lid behind the aluminum alloy, aluminum alloy main part 17 upper portion is equipped with circular heavy platform 20, thermopile sensor 18 sets up inside circular heavy platform 20, aluminum alloy main part 17 middle part is equipped with the second through-hole 21 that runs through aluminum alloy main part 17, aluminum alloy protecgulum 16 sets up and is equipped with the light-passing hole 22 that runs through aluminum alloy protecgulum 16 in aluminum alloy main part 17 upper portion and middle part.

All be equipped with a plurality of third through-holes 23 that run through self on lid 19 behind aluminum alloy protecgulum 16 and the aluminum alloy, be equipped with the screw hole 24 that corresponds with third through-hole 23 position on the aluminum alloy main part 17, be equipped with countersunk screw 25 in the screw hole 24, countersunk screw 25 fixes aluminum alloy protecgulum 16, aluminum alloy main part 17, thermopile sensor 18 and lid 19 behind the aluminum alloy for a whole.

The aluminum alloy main body 17 is provided with a top thread pad 27, an M4 hexagon socket head cap 28 matched with the top thread pad 27 and a shielding wire 26 arranged on one side of the aluminum alloy main body 17.

The utility model relates to a small laser power thermopile sensor's concrete implementation process as follows:

example 1: the specific implementation process of the thermopile sensor is as follows:

the aluminum alloy matrix 1 is a heat-conducting matrix, the middle adopts a low-heat-conductivity-coefficient film 2 as a support, the low-heat-conductivity-coefficient film is fixed in the aluminum alloy matrix 1 through the interference fit of a copper pressing ring 7, the copper layers are plated in the middle and the outer ring of a nylon film through a vacuum coating process, an absorber 6 is sprayed on a middle copper plating layer 3 through a plasma spraying process, the diameter of the absorber is slightly smaller than that of the middle copper plating layer 3, the outer copper plating layer 3 is in close contact with the copper pressing ring 7, a thermopile sensitive layer 5 is arranged on an insulating layer 4 and is arranged on the same surface as the absorber 6, the cold end and the hot end of the absorber are respectively positioned at the positions of the outer copper plating layer 3 and the inner copper plating layer 3, the sensitive layer and the copper pins 14 are connected through pure silver sheets 12 through conductive silver adhesive, the pure silver sheets 12 are positioned on the same surface of the thermopile sensitive layer 5, a notch is arranged on the copper pressing ring 7, so that the pure silver sheets 12 can be connected with the bottoms of the copper pins 14 in the binding post 29, the top of the copper pin 14 is arranged on the back of the substrate and is connected with a high-temperature-resistant lead to output a voltage signal.

Example 2: the specific implementation process of the laser power meter is as follows:

the aluminum alloy front cover 16 is installed on the aluminum alloy main body 17 through a countersunk screw 25, the thermopile sensor 18 is pressed on a circular sinking platform 20 inside the main body by the aluminum alloy front cover 16, the aluminum alloy rear cover 19 is also installed on the main body through the countersunk screw 25, and the copper needle 14 and the output shielding wire 26 are connected through a high-temperature resistant wire. By replacing different cooling parts, such as a radiating fin with a larger size, cooling by a fan and water cooling, the power meter with different maximum measuring powers is manufactured. According to different use scenes, a signal conditioning circuit can be arranged in the device.

The present invention and the embodiments thereof have been described above, but the description is not limited thereto, and the embodiment shown in the drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should understand that they should not be limited to the embodiments described above, and that they can design the similar structure and embodiments without departing from the spirit of the invention.

Claims

1. A micro laser power thermopile sensor is characterized in that: the thermoelectric module comprises an aluminum alloy substrate (1), a low-thermal-conductivity-coefficient film (2), a copper plating layer (3), an insulating layer (4), a thermopile sensitive layer (5), an absorber (6) and a copper pressing ring (7);

the aluminum alloy substrate (1) is of a circular ring step structure, the aluminum alloy substrate (1) comprises a first step (8) and a second step (9), the outer side diameters of the first step (8) and the second step (9) are the same, and the inner diameter of the second step (9) is larger than that of the first step (8); the low coefficient of thermal conductivity film (2) are disk form and diameter slightly less than second step (9) internal diameter, low coefficient of thermal conductivity film (2) are placed on first step (8) and become the concentric circles with aluminum alloy base member (1), copper coating (3) outer lane is the ring form, and the center is the disk form, and center disk diameter slightly is greater than absorber (6) diameter, copper coating (3) set up in low coefficient of thermal conductivity film (2) upper portion, insulating layer (4) are disk form and set up in copper coating (3) upper portion, thermopile sensitive layer (5) set up in insulating layer (4) upper portion, thermopile sensitive layer (5) both ends are located copper coating (3) outer lane and interior round position, insulating layer (4) top, thermopile sensitive layer (5) middle part is located in absorber (6), copper clamping ring (7) set up in insulating layer (4) upper portion, the inner diameter of the copper pressing ring (7) is larger than the outer diameter of the sensitive layer, the copper pressing ring (7) is not in contact with the sensitive layer, and the copper pressing ring (7) is in interference fit with the aluminum alloy base body (1).

2. A microlaser power thermopile sensor of claim 1, wherein: the thermopile sensitive layer (5) comprises a thermopile positive layer (10) and a thermopile negative layer (11), wherein the thermopile negative layer (11) and the thermopile positive layer (10) are mutually symmetrical and closely connected.

3. A microlaser power thermopile sensor of claim 2, wherein: be equipped with pure silver piece (12) on thermopile sensitive layer (5), pure silver piece (12) one end lower part is equipped with terminal (29) that run through aluminum alloy base member (1), terminal (29) are including insulating seat (13) and run through copper needle (14) of insulating seat (13).

4. A microlaser power thermopile sensor of claim 1, wherein: and the copper plating layer (3) and the low-heat-conductivity-coefficient film (2) are provided with first through holes (15) matched with the insulating base (13).

5. A microlaser power thermopile sensor of claim 3, wherein: the insulating seat (13) is a polytetrafluoroethylene insulating seat (13).

6. A microlaser power thermopile sensor of claim 1, wherein: the low-heat-conductivity-coefficient film (2) is made of a nylon material.

7. A laser power meter with a thermopile sensor built-in of any one of claims 1-6, comprising an aluminum alloy front cover (16), an aluminum alloy body (17), a thermopile sensor (18), and an aluminum alloy rear cover (19), characterized in that: aluminum alloy main part (17) set up lid (19) upper portion behind the aluminum alloy, aluminum alloy main part (17) upper portion is equipped with circular heavy platform (20), thermopile sensor (18) set up in circular heavy platform (20) inside, aluminum alloy main part (17) middle part is equipped with second through-hole (21) that run through aluminum alloy main part (17), aluminum alloy protecgulum (16) set up and are equipped with logical unthreaded hole (22) that run through aluminum alloy protecgulum (16) in aluminum alloy main part (17) upper portion and middle part.

8. The laser power meter with the built-in thermopile sensor of claim 7, wherein: all be equipped with a plurality of third through-holes (23) that run through self on lid (19) behind aluminum alloy protecgulum (16) and the aluminum alloy, be equipped with screw hole (24) that correspond with third through-hole (23) position on aluminum alloy main part (17), be equipped with countersunk screw (25) in screw hole (24), countersunk screw (25) are fixed as a whole with aluminum alloy protecgulum (16), aluminum alloy main part (17), thermopile sensor (18) and aluminum alloy rear cover (19).

9. The laser power meter with the built-in thermopile sensor of claim 8, wherein: the aluminum alloy main body (17) is provided with a top wire pad (27), M4 inner hexagonal top wires (28) matched with the top wire pad (27) and a shielding wire (26) arranged on one side of the aluminum alloy main body (17).