JPH11211561A - Infrared sensor and method of manufacturing the same - Google Patents

Abstract

(57) [Problem] To provide an infrared sensor and a method for manufacturing the same, which prevent a decrease in sensitivity and are easy to handle during assembly. An infrared sensor having a lens (2) and a reflecting mirror (3) disposed on the front surface of an infrared detecting element (1), wherein the lens (2) and the reflecting mirror substrate (3a) are made of high-density polythylene resin.
Are formed integrally, and the reflecting mirror 3 has a reflecting film 3b formed on the surface of the reflecting mirror base material 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared sensor and a method for manufacturing the same.

[0002]

2. Description of the Related Art Hitherto, infrared sensors such as human body detection sensors have used a lens or a reflecting mirror in front of a detection element (pyroelectric element) in order to secure a required detection area such as a wide detection range. Was. However, these lenses and reflecting mirrors are separate parts in which different materials are used for the respective substrates in view of the required characteristics. That is, the lens is made of high-density polyethylene or a plastic material having a high transmittance for infrared wavelengths emitted by the human body.
A base material is formed of a BS resin or a plastic material having good surface smoothness and plating properties, and a Cr thin film or a smooth metal thin film having a high infrared reflectance is formed on the reflection surface by plating.

[0003]

However, since the lens and the reflector base material are made of different materials, their molding shrinkage ratios are different. Therefore, depending on the case, the sensitivity of the infrared sensor may be lowered, or the infrared sensor may be a separate part. There were problems such as the need for man-hours in parts handling. In addition, the plating process for forming the infrared reflective metal thin film on the reflector base material has a problem that a long processing time is required due to a large number of processing steps, and a large number of man-hours are required for environmental protection due to the wet method. .

Further, C having a higher infrared reflectance than Cr has
When a high-infrared reflective metal thin film made of u, Al, or the like is formed, the high-infrared reflective metal thin film is oxidized due to its easy oxidizability, and the infrared reflectance is reduced, which causes a problem that the sensitivity of the infrared sensor is reduced. . Further, when a top coat is formed on a metal thin film to prevent oxidation, the number of treatment steps is increased and the infrared reflectance is reduced by the top coat, so that it has not been practically usable as an infrared sensor.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an infrared sensor which prevents a decrease in sensitivity and which is easy to handle during assembly, and a method of manufacturing the same.

[0006]

An infrared sensor according to claim 1, wherein a lens and a reflecting mirror are arranged in front of an infrared detecting element, wherein the lens and the reflecting mirror base are integrally formed of resin. The reflecting mirror is characterized in that a reflecting film is formed on the surface of the reflecting mirror base material.

According to the infrared sensor of the first aspect, since the lens and the reflecting mirror base are made of the same material, their molding shrinkage rates are the same, and the integration accuracy is improved by forming the lens and the reflecting mirror as an integral type. In addition, the sensitivity of the infrared sensor is not reduced, and the handling at the time of assembling becomes easier as compared with another part. Also, since it can be made into one part, molding can be reduced to one process.

[0008] The infrared sensor according to the second aspect is the first aspect.
In the above, the lens and the reflector base are connected via a bridge having a hinge structure, and the lens and the reflector base are bent by folding the hinge portion so as to overlap from a deployed state apart from each other, A lens and the reflector base are arranged in a predetermined positional relationship.

According to the infrared sensor of the second aspect, in addition to the same effects as the first aspect, it is impossible in the mold structure to perform molding in an arrangement that can be made compact such that a lens is covered on a reflecting mirror. The reflector and lens are arranged side-by-side and connected via a bridge, and the bridge is hinged by taking advantage of the characteristics of high-density polyethylene resin, which is a crystalline resin. Can be covered.

According to a third aspect of the present invention, there is provided a method of manufacturing an infrared sensor according to the first or second aspect, wherein the surface of the reflecting mirror substrate has a surface roughness of about 1 μm.
The reflective film is molded by a mold polished within
The film is formed by VD. According to the method of manufacturing an infrared sensor according to the third aspect, since the film is formed by PVD, the processing step is completed in one step, and the processing time is short. Since PVD is a dry process, it is suitable for environmental protection.

According to a fourth aspect of the present invention, there is provided a method of manufacturing an infrared sensor according to the first or second aspect, wherein the reflection surface is formed in a mold for forming a surface of the reflector base. Wherein the metal film is positioned in advance and the metal film is adhered to the surface of the reflector base when the reflector base is formed. According to the method of manufacturing an infrared sensor according to the fourth aspect, since the reflecting mirror base material and the metal film are adhered by molding, a surface treatment step by plating is unnecessary, which is suitable for environmental protection.

According to a fifth aspect of the present invention, there is provided a method for manufacturing an infrared sensor according to the first or second aspect, wherein the reflection surface is formed in a mold for forming a surface of the reflector base. The metal film is positioned in advance, and the metal film is sandwiched by the high-density polyethylene resin on the surface of the reflector substrate when the reflector substrate is formed.

According to the method of manufacturing an infrared sensor according to the fifth aspect of the present invention, since the metal film is sandwiched between the high-density polyethylene resin and the same material as the reflector base material on the surface of the reflector base material, The oxidation of the high-infrared reflective metal thin film can be prevented without substantially lowering the infrared reflectance.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an infrared sensor, in which a lens 2 and a reflecting mirror 3 are provided in front of an infrared detecting element 1.
Has been arranged. Arrows indicate infrared rays incident on the infrared detecting element 1. The infrared rays are condensed on the infrared detecting element 1 such as a pyroelectric element by the light condensing action of the lens 2 and the reflection of the reflecting mirror 3, thereby increasing the sensitivity. The reflecting mirror 3 is an infrared ray parallel to the mounting surface of the infrared sensor.
15 μm infrared rays are efficiently reflected and reach the detection element.

FIGS. 2 and 3 show a lens 2 and a reflecting mirror 3, in which the lens 2 and the reflecting mirror base 3a are integrally formed of a resin such as a high-density polythylene resin, and are formed on the surface of the reflecting mirror base 3a. The reflection film 3b is formed. In the embodiment, the lens 2 and the reflector base 3a are connected via, for example, two or more bridges 4 having a hinge structure, and FIG. 2 and FIG. 3 in which the lens 2 and the reflector base 3a are apart from each other. By folding the hinge portion 4a of the bridge 4 from the unfolded state so that the two overlap as shown by the arrow A, the lens 2 and the reflector base 3a as shown in FIG.
Are arranged in a predetermined positional relationship.

The portion of the reflecting mirror base material 3a is provided with a rectangular substrate portion 5 serving as an attachment portion, and a pair of projections projecting from the center of the substrate portion 5 in the longitudinal direction so as to face in the lateral direction in plan view. Side plate 6
And a reflector supporting body are formed. Reflector base material 3a
Is formed between the opposing surfaces of the pair of side plates 6 and is formed in a plate shape having an inverted C-shaped cross section. The bridge 4 is connected to one end in the longitudinal direction of the substrate portion 5, and the hinge portion 4a is formed of a thin wall so that it can be bent at a predetermined position. The lens 2 has a substantially hollow trapezoidal shape with an open bottom surface. The bottom surface is rectangular, and a flange 2b is formed on the periphery. The other end of the bridge 4 is connected to one end in the longitudinal direction. The hollow portion 2a of the lens 2 faces in the same direction as the side plate 6, and the inner top surface and the inner side surface are a condensing lens having, for example, a convex shape. When the hinge portion 4a is bent in the direction of arrow A, the substrate portion 5 and the flange portion 2b overlap each other, and the reflecting mirror 3 is located in the hollow portion of the lens 2 so that the lens 2 overlaps the reflecting mirror 3 as shown in FIG. .
Note that the reflector supporting body may be formed in a rectangular tube portion instead of the pair of side plates, and the reflector base 3a may be provided in the longitudinal direction inside the rectangular tube portion.

As described above, the lens 2 and the reflecting mirror 3 are connected via the bridge 4 as shown in FIG.
A part is formed in one shot in a mold by injection molding. The material of the integrally molded product of the lens 2 and the reflector base material 3a is not particularly limited as long as it is a high-density polythylene resin having a high infrared transmittance. In addition to the injection method, the molding method includes compression molding, vacuum molding, casting, and the like. However, the method is not particularly limited as long as the shape of the lens 2 and the reflecting mirror 3 can be accurately reproduced.

The bridge 4 is provided with a thin hinge structure as described above.
The reflecting mirror 3 is arranged inside the lens 2 by bending a so that a required infrared light distribution can be obtained. In this case, two or more bridges 4 are provided in consideration of rigidity in directions other than the bending direction, and the reflecting surface 3b of the reflecting mirror base material 3a faces the same direction as the lens outer surface 2c. The positional relationship between the lens 2 and the reflecting mirror 3 is not particularly limited as long as the reflecting mirror 3 is arranged at a required position at the time of bending.

The lens surface formed on the inner surface of the hollow portion 2a of the lens 2 is formed into an aspherical shape so as to obtain a required infrared light distribution, and the lens surface is mirror-finished. The reflecting mirror 3 is composed of a reflecting surface 3b for condensing the infrared light distributed by some of the lenses 2 on the pyroelectric element, and a structure such as a substrate portion 5 for mounting the lens 2. The reflecting surface 3b is designed at an angle so as to obtain a required light distribution, and is mirror-finished by molding so as to obtain a required infrared reflectance. A high-infrared reflective metal film having a high infrared reflectivity is directly formed on the reflective surface 3b as a reflective film by PVD (Physical Vapor Deposition).

FIG. 4 shows a configuration diagram of the reflecting mirror 3. The metal film 3c which is a reflection film formed on the surface of the reflector base material 3a is C
r is used. The thickness and the number of layers of the high-infrared reflective metal film 3c are not particularly limited as long as predetermined optical characteristics can be obtained. For example, in another embodiment shown in FIG. 5, the number of layers of the high-infrared reflective metal film 3c is two, consisting of Cu formed on the surface of the reflector base material 3a and Cr formed thereon. The material of the high-infrared reflective metal film 3c is A
l, Cr, Ag, Ni, Pt and the like are used, but there is no limitation as long as predetermined optical characteristics can be obtained. The PVD for forming the high-infrared reflective metal film 3c includes, but is not limited to, a vacuum deposition method, a sputtering method, an ion plating method, and a beam method.

In this case, as a method of manufacturing the reflecting mirror 3, the surface of the reflecting mirror substrate 3a is formed by, for example, a mold polished to a surface roughness of about 1 μm or less, and the metal film 3c is formed by PVD. preferable. According to this embodiment, since the lens 2 and the reflecting mirror base material 3a are made of the same material, their molding shrinkage rates are the same. Sensitivity is not reduced, and handling during assembly is easier than with other parts. Also, since it can be made into one part, molding can be reduced to one process.

Further, it is impossible to mold in an arrangement which can be downsized such that the lens 2 is put on the reflecting mirror 3 because of the mold structure.
The reflecting mirror 3 and the lens 2 are arranged side by side and connected via a bridge 4, and the bridge 4 is easily bent by making the bridge 4 into a thin hinge structure by utilizing the characteristics of a high-density polyethylene resin which is a crystalline resin. Thus, the lens 2 can be put on the reflecting mirror 3. Further, when the lens 2 and the reflector base 3a are connected by one bridge 4, there is a possibility that lateral shaking or twisting may occur during molding or assembling. However, when the number is two or more, the rigidity in the lateral direction increases, so that the lateral displacement and the torsion do not occur.

Further, since the reflection film is formed by PVD, the processing step is completed in one step, and the processing time is short. PVD is a dry process and is suitable for environmental protection. A second embodiment of the present invention will be described with reference to FIGS.
This infrared sensor is different from the first embodiment in that the hinge portion 4a is connected not in the longitudinal direction but in the short direction of the substrate portion 5 and the flange portion 2b, and the other components are the same as those in the first embodiment. is there.

As a method of manufacturing the reflecting mirror according to the first and second embodiments, a metal film 3c serving as a reflecting film for forming a reflecting surface is formed in a mold for forming a surface of a reflecting mirror base 3a.
Is positioned in advance, and a metal film 3c is adhered to the surface of the reflector base 3a when the reflector base 3a is formed. As a result, the reflector base material 3a and the metal film 3c are adhered by molding, so that a surface treatment step by plating is not required, which is suitable for environmental protection.

As a method of manufacturing a reflector according to another embodiment, a metal film 3c for forming a reflection surface is previously positioned in a mold for forming a surface of a reflector base 3a, and is made of a high-density polyethylene resin. The metal film 3c is sandwiched by a high-density polyethylene resin on the surface of the reflector base 3a when the reflector base 3a is formed. FIG. 8 shows a metal film 3c in which Ni is sandwiched in a sandwich shape, and 3e is a high-density polyethylene resin on the surface of the metal film 3c.

FIG. 9 similarly shows a structure in which Cu is sandwiched as a metal film 3c. According to these embodiments, the reflector base 3a is provided on the surface of the reflector base 3a.
Since the metal film 3c is sandwiched between the high-density polyethylene resins 3e of the same material as that of the above, the high-infrared reflective metal thin film 3 is hardly reduced in infrared reflectance.
The oxidation of c can be prevented.

FIGS. 10 to 29 show a sensor remote controller to which the third embodiment of the present invention is applied. That is, the sensor remote controller is disposed at a position away from the lighting equipment 11 as indicated by reference numeral 10 in FIG. 10B, and detects infrared rays emitted by the person 13. Reference numeral 12 denotes a detection area of the sensor remote controller 10 indicated by oblique lines, reference numeral 14 denotes a transmission signal of the sensor remote controller 10, and reference numeral 15 denotes a space illuminated by the lighting fixture 11. As shown in FIG.
In the case of a fixture / sensor integrated type in which 0 'is provided in the lighting fixture 11, the detection area 12 is limited to the vicinity of the lighting fixture 11, but in this embodiment, the detection range is widened. In addition, there are advantages such as reduced construction, reduced wiring, use of MT in sensor equipment, and improved freedom in setting a detection range.

FIG. 11 shows an example in which a plurality of luminaires 11a and 11b such as an inner entrance are operated by a sensor remote controller 10. In addition, it is possible to correspond to the inclined ceiling,
It is also possible to control the lighting fixtures 11a and 11b individually. FIG. 12 is an exploded perspective view of the sensor remote controller. 5
Reference numeral 0 denotes a mounting base formed of, for example, a sheet metal, reference numeral 51 denotes a hook-shaped mounting portion, and reference numeral 52 denotes a mounting base resin. 53 is a lower cover, 54 is an opening to be locked to the mounting portion 51, and 55 is a printed circuit board mounted on the lower cover 53, on which the infrared detecting element 1 is mounted.

Reference numeral 56 denotes a plurality of transmitting elements for transmitting infrared light, ultrasonic waves, light beams, etc. using, for example, light emitting diodes (LEDs) directed to a plurality of directions, 57 denotes a sensor control switch mounted on a printed circuit board 55, and 58 denotes a sensor controlling switch. Switches for various manual operations. 59 is an upper cover that covers the lower cover 53, 60 is an opening that exposes the infrared radiating element, 61 is a light emitting cover that covers the opening 60, and 62 is the first embodiment that is located on the front side of the infrared detecting element 1. A condensing member including the lens 2 and the reflecting mirror 3 shown in FIG.
7 is a resin button for operating 7, 64 is a switch group 58
A switch hole for operating the switch, for example, four AA
Alkaline battery. Numeral 78 is a knob of a rotary control means which is provided in the switch group 58 by operating knobs made of resin.

Reference numeral 66 denotes a panel for opening and closing the surface of the upper cover 59, and is rotatably connected to a lower end of the upper cover 59 by a shaft (not shown). 67 is an exposure hole of the operation button 63 made of resin, and 68 is a sensor decorative sheet of the light collecting member 62. FIG. 13 shows a receiver for receiving an infrared ray or the like, which is a signal of the transmission element 56 of the sensor remote controller, and includes a light receiving section (FIG. 13A) and a power supply section (FIG. 13B).
Is a light receiving case, 71 is a CdS cover, 72 is a charging section protection cover, 73 is a tape wire, 74 is a mounting section, 76 is a printed circuit board of a power supply section, and 77 is a heat sink. The receiver is attached to a control target device such as the above-mentioned lighting device, but may be provided separately from the device in some cases.

FIG. 14 shows the front of the sensor remote controller with the panel 66 closed, and FIG. 15 shows the sensor remote controller panel 60, upper cover 59, and light emitting cover 61 from the front. The transmitting elements 56 are arranged in a row in a row, and are arranged upward as shown in FIG.
The central one is arranged almost perpendicular to the printed circuit board 55, the ones on both sides are inclined so as to be directed outward by about 90 degrees, and the ones on both sides thereof are tilted outwardly by about 110 degrees from each other. Further, both outer sides are inclined so that they are directed outward by about 130 degrees. Thereby, a horizontal detection area of about 170 to 180 ° is obtained. Reference numeral 80 denotes a conductive plate of a battery electrode, which is wired to the printed circuit board 55.

FIG. 16 is a cross section of the sensor remote controller.
FIG. 9 shows an arrangement relationship between the light-condensing member 62 and the infrared detecting element 1;
Also, the positional relationship between the operation button 63 and the switch 57 is shown. FIG. 17 shows the bottom surface of the sensor remote controller.
FIG. 18 shows a vertical section of the sensor remote controller, in which each infrared radiation element 56 is inclined upward, for example, at about 45 degrees, and transmits the light toward the receiver of the lighting fixture located on the ceiling. 81 is a rotation axis of the panel 60. FIG. 19 shows a side view of the sensor remote controller.

FIGS. 20 to 26 show the light-collecting element 62.
Portions common to the first embodiment and the like are denoted by the same reference numerals. 45 is a positioning projection, and 46 is a mounting hole. Further, in the lens 2 shown in FIGS. 24 and 25 in which a part of FIG. 20 is enlarged, 30 and 31 are lens portions formed at the center of the inner top surface of the hollow portion 2a, and 32 and 32 are on both sides of the inner top surface. The symmetrically formed lens portions 35 to 38 are respectively symmetrically formed on the inner surface. As shown in FIGS. 24 and 25, in each of the lens portions, a black circle indicates a principal point position, and a triangle indicates a focal position H at which the infrared detecting element 1 is located. However, as shown in FIG. 26, the focal positions of the lens portions 36 and 38 are symmetrical positions K of the focal position H with respect to the opposing reflecting surface 3b. 24 and 25, the focal position H is on a plane including the principal point positions of the lens units 30 and 31, and the principal point of the lens units 33 and 37 is, for example, 27.2 with respect to a normal line perpendicular to the plane. It is inclined by 5 degrees, and similarly, the principal points of the lens portions 32 and 35 are, for example, 53.
It is inclined 6 degrees. In the cross section of the lens 2 in FIG.
A line connecting the lens units 32 and 33 and the focal position H is inclined by, for example, 26.3 degrees with respect to a plane connecting the principal points of the lens units 30 and 31 and the focal position H, and the line connecting the lens units 36 and 38 and the focal position H is inclined. The line connecting H is inclined, for example, by 52.7 degrees.

FIGS. 27 to 29 show the viewing angles of the detection area 12 by the lens 2 and the reflecting mirror 3 as described above. Figure 27 shows the appearance of the detection area 12, FIG. 28 shows the detection area 12 as viewed in plan hatched, open angle M ₁ is approximately 17
It has a fan shape from 0 to 180 degrees. Figure 29 (a) the inclination angle M ₂ is, for example, 6 degrees downward with respect to the horizontal plane of the upper surface of the detection area 12 indicated by hatching indicates the lower surface of the lower inclination angle M ₃ for example 36 degrees, FIG. (B) horizontal an example each opening angle M ₄ is approximately 85 degrees to both sides of the projecting direction of the lens 2 in intended to illustrate the direction of the limits of the detection area. In any case, the trapezoidal top surface of the lens 2 and the inclined surfaces on both sides of the trapezoidal surface, and the inside of each corner 2f by a certain distance, for example, about 1 mm, are the boundaries of the incident range.

[0035]

According to the infrared sensor of the first aspect,
Since the lens and the reflector base material are made of the same material, their molding shrinkage rates are the same, and by integrating them, the positioning accuracy at the time of assembly is increased, and the sensitivity of the infrared sensor is not reduced, Handling during assembling is easier than for separate parts. Also, since it can be made into one part, molding can be reduced to one process.

According to the infrared sensor of the second aspect, in addition to the same effects as those of the first aspect, it is impossible in the mold structure to perform molding in an arrangement that can be miniaturized such that a lens is put on the reflecting mirror. The reflector and lens are arranged side-by-side and connected via a bridge, and the bridge is hinged by taking advantage of the characteristics of high-density polyethylene resin, which is a crystalline resin. Can be covered.

According to the method of manufacturing an infrared sensor according to the third aspect, since the film is formed by PVD, the processing step is completed in one step, and the processing time is short. Since PVD is a dry process, it is suitable for environmental protection. . According to the method of manufacturing an infrared sensor according to the fourth aspect, since the reflecting mirror base material and the metal film are adhered by molding, a surface treatment step by plating is unnecessary, which is suitable for environmental protection.

According to the method for manufacturing an infrared sensor according to the fifth aspect, since the metal film is sandwiched by the high-density polyethylene resin of the same material as the reflector base material on the surface of the reflector base material, The oxidation of the high-infrared reflective metal thin film can be prevented without substantially lowering the infrared reflectance.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a first embodiment of the present invention.

FIG. 2 is a side view of a deployed state of a lens and a reflecting mirror.

FIG. 3 is a plan view thereof.

FIG. 4 is a partial sectional view of a reflecting mirror.

FIG. 5 is a partial sectional view of another embodiment of the reflector;

FIG. 6 is a plan view showing a state where a lens and a reflecting mirror according to a second embodiment are expanded.

FIG. 7 is a side view thereof.

FIG. 8 is a partial sectional view of still another embodiment of the reflector;

FIG. 9 is a partial sectional view of still another embodiment of the reflector;

FIG. 10 is an explanatory diagram illustrating an arrangement position and a detection area of a sensor remote controller according to a third embodiment.

FIG. 11 is an explanatory diagram showing a transmission range of a sensor remote controller.

FIG. 12 is an exploded perspective view of the sensor remote controller.

FIG. 13 is a perspective view of a light receiving section (a) and a power supply section (b) of a receiver for a transmission signal.

FIG. 14 is a front view of the sensor remote controller.

FIG. 15 is a front view showing a configuration of a sensor remote controller.

FIG. 16 is a cross-sectional view of the sensor remote controller.

FIG. 17 is a bottom view of the sensor remote controller.

FIG. 18 is a longitudinal sectional view of the sensor remote controller.

FIG. 19 is a side view of the sensor remote controller.

20 (a) is a front view of a developed state of a light collecting member including a lens and a reflecting mirror, and FIG. 20 (b) is a sectional view of the reflecting mirror taken along line AA.

FIG. 21 is a bottom view thereof.

FIG. 22 is a rear view of the assembly of the lens and the reflecting mirror;

FIG. 23 is a side view of FIG. 20;

FIG. 24 is a detailed view of a central portion of the lens.

FIG. 25 is a detailed view of a side portion of the lens.

FIG. 26 is an explanatory diagram showing a principal point position and a focal position of a lens.

FIG. 27 is an explanatory diagram showing a viewing angle of a sensor remote controller.

FIG. 28 is an explanatory diagram showing a horizontal viewing angle.

FIG. 29 is an explanatory diagram showing a vertical viewing angle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Infrared detecting element 2 Lens 3 Reflecting mirror 3b Reflecting surface 3c Metal film (reflecting film) 4 Bridge 4a Hinge part

Claims (5)

[Claims] 1. An infrared sensor in which a lens and a reflector are arranged on the front surface of an infrared detecting element, wherein the lens and the reflector base are integrally formed of resin, and the reflector is a surface of the reflector base. An infrared sensor characterized in that a reflective film is formed on the infrared sensor. 2. The lens and the reflector substrate are connected via a bridge having a hinge structure, and the hinge portion is bent so that the lens and the reflector substrate overlap each other from a separated development state. The infrared sensor according to claim 1, wherein the lens and the reflecting mirror base material are arranged in a predetermined positional relationship. 3. The method of manufacturing an infrared sensor according to claim 1, wherein the surface of the reflector base is formed by a mold polished to a surface roughness of about 1 μm or less, and the reflection film is formed. A method for manufacturing an infrared sensor, comprising forming a film by PVD. 4. The method for manufacturing an infrared sensor according to claim 1, wherein a metal film for forming a reflection surface is previously positioned in a mold for forming a surface of the reflector base material, and the reflection is performed. A method for manufacturing an infrared sensor, wherein the metal film is adhered to a surface of the reflecting mirror substrate when the mirror substrate is formed. 5. The method for manufacturing an infrared sensor according to claim 1, wherein a metal film for forming a reflection surface is previously positioned in a mold for forming a surface of the reflector base material, and the reflection is performed. A method for manufacturing an infrared sensor, wherein the metal film is sandwiched between the high-density polyethylene resin and the surface of the reflecting mirror substrate when the mirror substrate is formed.