TWI685681B - Infrared diffuser - Google Patents

Abstract

An infrared filter includes a photo-absorption film and a first optical film. The photo-absorption film includes a binder and a plurality of infrared absorption particles, where the infrared absorption particles are inorganic and distributed in the binder. The mean agglomerate particle size of the infrared absorption particles is less than 80nm. The first optical film is formed on one side of the photo-absorption film. The thickness of the infrared filter ranges between 10μm and 500μm, whereas the infrared cut-on wavelength of the infrared filter ranges between 600nm and 650nm. An average transmittance of the infrared filter which ranges in wavelength between 700nm and 1100nm is less than 1%, whereas an average transmittance of the infrared filter which ranges in wavelength between 430nm and 580nm is larger than 75%.

Description

Infrared filter

The present invention relates to an optical element, and particularly to an optical filter.

Most current mobile devices, such as smartphones and tablets, have been equipped with an image sensor to enable the mobile device to have an image capturing function. The above image sensor is usually a complementary metal-oxide semiconductor (Complementary Metal-Oxide-Semiconductor, hereinafter referred to as CMOS) image sensor (CMOS Image Sensor, CIS), which is a chip package (chip package). The wavelength of response of the CMOS chip of the CMOS image sensor covers not only visible light, but also infrared light and ultraviolet light. In order to prevent infrared light and ultraviolet light from interfering with the image captured by the image sensor, a filter is generally installed in the image sensor to filter out unnecessary infrared light and ultraviolet light.

Generally speaking, there are two types of infrared light filters installed in the image sensor: one is a blue glass infrared light absorption sheet, and the other is an infrared light absorption resin film. The blue glass infrared light absorption sheet has excellent optical performance, and can almost completely absorb infrared light in the wavelength range of 700 nanometers (nm) to 1100 nanometers to effectively filter out infrared light, and the blue glass infrared light absorption sheet also has Good visible light transmittance. In addition, the main material of the blue glass infrared light absorption sheet is glass, so it also has the advantage of high temperature resistance, that is, the blue glass infrared light absorption sheet can withstand the high temperature environment of reflow (reflow). However, the manufacturing of the blue glass infrared light absorbing sheet requires multiple steps, including melting, forming, annealing, cutting, polishing, and coating. Therefore, the blue glass infrared light absorbing sheet has the disadvantages of complicated manufacturing and difficult mass production.

Since the image sensor equipped with the mobile device is a chip package, its thickness is usually less than or equal to 2 millimeters (mm), so the infrared light filter used in the image sensor must have a sufficiently thin thickness, otherwise The infrared filter cannot be installed in the image sensor. However, the processing of the blue glass infrared light absorbing sheet is difficult, and the thickness of the blue glass infrared light absorbing sheet is difficult to meet the requirements of the image sensor. In addition, the main material of the blue glass infrared light absorption sheet is glass, so the blue glass infrared light absorption sheet also has the disadvantage of being fragile like ordinary glass. Even if the blue glass infrared light absorbing sheet has a sufficiently thin thickness to be installed in the image sensor, the blue glass infrared light absorbing sheet may be easily broken due to accidental impact or falling of the mobile device.

The infrared light absorbing resin film has the advantages of thin thickness, easy processing and easy mass production, and the main material of the infrared light absorbing resin film is a polymer material, so the infrared light absorbing resin film has toughness. Even if the mobile device is accidentally hit or dropped, the infrared light absorbing resin film in the mobile device will not be broken. However, the optical performance of the infrared light absorbing resin film is far inferior to the blue glass infrared light absorbing sheet. The infrared light absorbing resin film cannot effectively absorb infrared light from 700 nanometers to 1100 nanometers. As a result, the infrared light absorbing resin film allows part of the infrared light to penetrate, causing the image capture of the image sensor to be interfered by infrared light. In addition, the main material of the infrared light absorbing resin film is a polymer material, so the infrared light absorbing resin film does not have the advantage of high temperature resistance. Therefore, the infrared light absorbing resin film is easily deformed or deteriorated in a high-temperature environment.

The invention provides an infrared light filter, which can not only effectively filter infrared light in the wavelength range of 700 nanometers to 1100 nanometers, but also has a sufficiently thin thickness so as to be suitable for installation in images used in existing mobile devices Inside the sensor.

The infrared light filter provided by the present invention includes a light absorption film and a first optical film. The light-absorbing film includes a binder and a plurality of infrared light-absorbing particles. These infrared light absorbing particles are distributed in the bonding material, and are all inorganic materials, wherein the average agglomerate particle size of these infrared light absorbing particles is less than 80 nanometers. The first optical film is formed on the side of the light absorbing film, wherein the thickness of the infrared filter is between 10 microns and 500 microns, and the infrared cut-off wavelength of the infrared filter is (infrared cut- on wavelength) between 600 nm and 650 nm. The average transmittance of the infrared filter in the wavelength range of 700 nm to 1100 nm is less than 1%, and the average transmittance in the wavelength range of 430 nm to 580 nm is greater than 75%.

In an embodiment of the invention, the infrared light absorbing particles are amorphous particles.

In an embodiment of the invention, the weight percentage between the infrared light absorbing particles and the bonding material is between 1% and 80%.

In an embodiment of the invention, the infrared light absorbing particles are blue glass particles.

In an embodiment of the invention, the light absorbing film further includes an infrared light absorbing dye, and the infrared light absorbing dye is distributed in the bonding material.

In an embodiment of the present invention, the light absorbing film further includes an ultraviolet light absorbing dye, and the ultraviolet light absorbing dye is distributed in the bonding material.

In an embodiment of the invention, the light absorbing film further includes infrared light absorbing dye and ultraviolet light absorbing dye, and both the infrared light absorbing dye and the ultraviolet light absorbing dye are distributed in the bonding material.

In an embodiment of the invention, the bonding material includes an organic material.

In an embodiment of the invention, the bonding material includes an inorganic material.

In an embodiment of the invention, the infrared light filter further includes a second optical film formed on one side of the light absorption film.

In an embodiment of the invention, the light absorption film is located between the first optical film and the second optical film.

In an embodiment of the invention, the melting point of these infrared light absorbing particles is less than 850°C.

In an embodiment of the invention, the bonding material includes polyimide (Polyimide, PI) or polycarbonate (Polycarbonate, PC).

In an embodiment of the invention, the ultraviolet cut-off wavelength of the infrared filter is between 410 nm and 420 nm.

In an embodiment of the present invention, the thermal shrinkage of the light-absorbing film is less than or equal to 0.15%.

In an embodiment of the present invention, the thermal softening temperature of the light-absorbing film is greater than or equal to 160°C.

In an embodiment of the present invention, the bending strength of the light-absorbing film is between 90 MPa and 110 MPa.

In an embodiment of the present invention, the average transmittance of the light absorption film in the wavelength range of 350 nm to 395 nm is less than or equal to 0.15%, and the light absorption film in the wavelength range of 430 nm to 450 nm The average penetration rate is greater than 78%.

In an embodiment of the invention, the average transmittance of the light-absorbing film in the wavelength range of 700 nm to 725 nm is less than 1.8%.

Based on the above, using these inorganic infrared light absorbing particles, the infrared light filter provided in at least one embodiment of the present invention can not only effectively filter infrared light in the wavelength range of 700 nm to 1100 nm, but also has Thickness between 10 microns and 500 microns. Therefore, the infrared light filter not only has a sufficiently thin thickness to be installed in the image sensor of the existing mobile device, but also can effectively filter out infrared light to avoid infrared light from interfering with the image capture of the image sensor To improve image quality.

To make the above and other objects, features, and advantages of the present invention more comprehensible, embodiments are described below in conjunction with the accompanying drawings, which are described in detail below.

FIG. 1A is a schematic cross-sectional view of an infrared light filter according to an embodiment of the invention. Referring to FIG. 1A, the infrared light filter 100 includes a light absorption film 110 and a first optical film 121, wherein the first optical film 121 is formed on one side of the light absorption film 110, that is, the light absorption film 110 and the first optical film 121 Stacked on top of each other. The first optical film 121 may be an anti-reflection layer or an interference filter film. When the first optical film 121 is an anti-reflection layer, the first optical film 121 can reduce the reflectance of the infrared light filter 100, where the first optical film 121 may be a multilayer film or a sub-wavelength structure. When the first optical film 121 is an interference filter film, the first optical film 121 can enhance the ability to filter out invisible light (such as infrared light or ultraviolet light).

The light absorbing film 110 includes a binding material 111 and a plurality of infrared light absorbing particles 112, wherein the infrared light absorbing particles 112 are distributed in the binding material 111 and are all inorganic, that is, the infrared light absorbing particles 112 are all inorganic materials. That is, these infrared light absorbing particles 112 are composed of an inorganic material, and may be blue glass particles, where the melting point of these infrared light absorbing particles 112 may be less than 850°C. These infrared light absorbing particles 112 are amorphous phase particles, wherein the amorphous phase particles described herein cover not only the amorphous state, but also nanocrystals. In other words, the infrared light absorbing particles 112 may also be nanocrystals. In addition, the weight percentage between the infrared light absorbing particles 112 and the bonding material 111 may be between 1% and 80%.

The infrared light absorbing particles 112 may be composed of a plurality of nano particles, where the nano particles are, for example, blue glass nano particles, that is, the blue glass particles may be formed of nano particles. The blue glass nanoparticles can be generated after the blue glass plate is crushed and ground, and the blue glass plate itself has the function of filtering infrared light. The average agglomerated particle diameter of these infrared light absorbing particles 112 is less than 80 nanometers, so these infrared light absorbing particles 112 are basically nano particles. The bonding material 111 includes at least one of an organic material and an inorganic material. That is, the bonding material 111 may be an organic material or an inorganic material, or a combination of both organic and inorganic materials. The above organic material may include polyimide (PI) or polycarbonate (PC), that is, the bonding material 111 may include polyimide or polycarbonate.

The infrared cut-off wavelength of the infrared filter 100 is between 600 nm and 650 nm, and the infrared cut-off wavelength of the infrared filter 100 is between 410 nm and 420 nm, where The cut-off wavelength (regardless of infrared cut-off wavelength and ultraviolet cut-off wavelength) mentioned in this specification refers to the wavelength corresponding to the filter when its transmittance is 50%. For example, when the wavelength of a certain infrared light is the cut-off wavelength of the infrared light of the filter (such as the infrared filter 100), the transmittance of the filter corresponding to this infrared light is basically 50%. Similarly, when the wavelength of a certain ultraviolet light is the cut-off wavelength of the ultraviolet light of the filter (for example, the infrared light filter 100), the transmittance of the filter corresponding to this ultraviolet light is basically 50%.

The thickness T1 of the infrared light filter 100 is between 10 μm and 500 μm, wherein the thickness T2 of the light absorption film 110 may be greater than or equal to 5 μm, but less than 500 μm, for example, 100 μm. Therefore, the infrared light filter 100 has a sufficiently thin thickness T1 so that the infrared light filter 100 can be built into the image sensor used in the existing mobile device. Secondly, the bending strength of the light absorption film 110 is between 90 MPa and 110 MPa, so the infrared light filter 100 has sufficient structural strength and is not easily bent or broken. Obviously, the infrared light filter 100 does not have the disadvantage that the existing blue glass infrared light absorber is fragile.

In terms of optical performance, the average transmittance of the infrared filter 100 in the wavelength range of 700 nm to 1100 nm is less than 1%, and the infrared filter 100 in the wavelength range of 430 nm to 580 nm The average penetration rate is greater than 75%. Therefore, the infrared light filter 100 not only can effectively filter out infrared light (for example, the wavelength is between 700 nm and 1100 nm), but also can make most of the visible light (for example, the wavelength between 430 nm and 580 nm) Time) penetration. In this way, the infrared filter 100 applied to the mobile device can effectively prevent infrared light from interfering with the image capture of the image sensor, and allows the image sensor to receive most of the visible light, thereby maintaining or enhancing the image sensor’s Image quality.

It can be seen that, compared with the existing blue glass infrared light absorption sheet, the infrared light filter 100 can not only be installed in the image sensor used in the existing mobile device, but also has sufficient structural strength. In this way, after the mobile device is accidentally impacted or dropped, the infrared light filter 100 installed in the mobile device is less likely to break. Secondly, the average transmittance of the infrared filter 100 in the wavelength range of 700 nm to 1100 nm is less than 1%, and this is close to the average transmittance of the existing blue glass infrared light absorber (at 700 nm to 1100 nm wavelength range). Compared with the existing infrared light absorbing resin film, it is obvious that the infrared light filter 100 can filter out infrared light more effectively, that is, the infrared light filter 100 has better optical performance than the existing infrared light absorbing resin film.

In the embodiment shown in FIG. 1A, the light absorbing film 110 may further include infrared light absorbing dye 113 and ultraviolet light absorbing dye 114, and both the infrared light absorbing dye 113 and the ultraviolet light absorbing dye 114 are distributed in the bonding material 111. The infrared light absorbing dye 113 can help improve the infrared light filter 100's ability to filter out infrared light. The ultraviolet light absorbing dye 114 can absorb ultraviolet light, so that the average transmittance of the light absorbing film 110 in the wavelength range of 350 nm to 395 nm can be less than or equal to 0.15%. In this way, the infrared light filter 100 can filter out not only infrared light but also ultraviolet light, so that the infrared light filter 100 can effectively prevent infrared light and ultraviolet light from interfering with image capture of the image sensor.

In particular, in the embodiment shown in FIG. 1A, the light absorbing film 110 includes an infrared light absorbing dye 113 and an ultraviolet light absorbing dye 114, but in other embodiments, the purpose of the infrared light filter 100 is seen Or as required, the light absorbing film 110 may include one of the infrared light absorbing dye 113 and the ultraviolet light absorbing dye 114, or even not include the infrared light absorbing dye 113 and the ultraviolet light absorbing dye 114. Therefore, the infrared light absorbing dye 113 and the ultraviolet light absorbing dye 114 shown in FIG. 1A are only used as an example, and do not limit the light absorbing film 110 to include the infrared light absorbing dye 113 and the ultraviolet light absorbing dye 114.

The light absorption film 110 of the infrared light filter 100 can have different optical performance, bending strength and thermal characteristics according to different weight percentages between the infrared light absorption particles 112 and the bonding material 111, as shown in the following table (1) Samples 1 to 6 of the light absorption film 110 shown. In particular, samples 1 to 6 are just a few examples of the infrared filter 100, and do not limit the weight percentage between the infrared light absorbing particles 112 and the binding material 111 as shown in Table (1). Table I) Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Weight percentage between infrared light absorbing particles 112 and bonding material 111 (W%) 5w% 10w% 15w% 20w% 25w% 30w% The average transmittance of wavelength 700~725nm (%) 1.78 1.15 0.74 0.48 0.31 0.20 The average transmittance of wavelength 725~1200nm (%) 51.88 32.26 20.40 13.11 8.54 5.64 Infrared cut-off wavelength (nm) 633 627 621 615 610 605 The average penetration rate of wavelength 350~395nm (%) 0.15 0.14 0.14 0.13 0.13 0.12 Ultraviolet cut-off wavelength (nm) 417 417 417 417 417 417 The average transmittance of wavelength 430~450nm (%) 82.16 81.66 81.17 80.68 80.19 79.71 Thermal softening temperature (℃) 160 170 175 173 171 166 Heat shrinkage at 160℃ (%) 0.15 ＜0.1 ＜0.1 ＜0.1 ＜0.1 ＜0.1 Flexural strength (MPa) 101 105 110 108 100 90

Please refer to FIG. 1B and table (1), where FIG. 1B is a schematic diagram of the transmission spectra of samples 1 to 6 in table (1), and the curves S1, S2, S3, S4, S5, and S6 in FIG. 1B represent the samples in order. 1, 2, 3, 4, 5 and 6 transmission spectra. As can be seen from FIG. 1B and Table (1), the average transmittance of the light absorption film 110 in the wavelength range of 350 nm to 395 nm can be less than 0.15%, so the infrared filter 100 can effectively filter out ultraviolet light . The average transmittance of the light absorption film 110 in the wavelength range of 700 nm to 725 nm is less than 1.8%, so the light absorption film 110 can effectively filter out infrared light in the wavelength range of 700 nm to 725 nm. The average transmittance of the infrared filter 100 in the wavelength range of 430 nm to 580 nm is greater than 75%, and the average transmittance of the light absorption film 110 in the range of wavelength 430 nm to 450 nm is greater than 78% Therefore, the light absorbing film 110 can allow most of the visible light to pass through to maintain or improve the image quality of the image sensor. In addition, in terms of bending strength and thermal characteristics, Table (1) reveals that the thermal shrinkage rate of the light absorbing film 110 can be less than or equal to 0.15%, and the thermal softening temperature of the light absorbing film 110 can be greater than or equal to 160°C. Compared with the existing infrared light absorbing resin film, the light absorbing film 110 has better heat resistance.

The above mainly describes the structure, materials, and characteristics of the infrared light filter 100. Next, a method of manufacturing the infrared light filter 100 will be explained. In detail, first, the light absorption film 110 is manufactured. After the light absorption film 110 is manufactured, the first optical film 121 is formed on the light absorption film 110, wherein the first optical film 121 can be formed by physical vapor deposition (PVD), such as evaporation (evaporation) deposition) or sputtering.

The manufacturing method of the light absorbing film 110 can adopt the following steps. First, make blue glass. Specifically, the blue glass can be made of metaphosphate materials, metal oxides and metal fluorides. After the metaphosphate materials, metal oxides and metal fluorides are uniformly mixed, they are placed in a crucible. After that, the materials placed in the crucible are heated in an atmospheric environment or a reducing atmosphere furnace, where the reducing atmosphere furnace can provide an oxygen atmosphere environment, so that these materials can be heated in an oxygen atmosphere environment. In addition, the temperature of the above-mentioned reducing atmosphere furnace can be controlled between 700°C and 1000°C.

Regarding the materials selected for the blue glass, metaphosphate materials include, for example, aluminum metaphosphate, magnesium metaphosphate, lithium metaphosphate, zinc metaphosphate and calcium metaphosphate, and carbonates such as calcium carbonate, barium carbonate and strontium carbonate are at least A material, that is, a metaphosphate material may be any composition of these materials. The metal oxide includes, for example, at least one of copper oxide, aluminum oxide, zinc oxide, and magnesium oxide, that is, the metal oxide may be any composition of these materials. The metal fluoride includes, for example, at least one of aluminum fluoride, magnesium fluoride, calcium fluoride, strontium fluoride, barium fluoride, and zinc fluoride, that is, the metal fluoride may be any composition of these materials.

The composition of the above blue glass includes, for example, phosphorus ions with a molar percentage (mol%) of 35 to 55%, aluminum ions with a molar percentage of 0 to 18%, alkali metal ions with a molar percentage of 5 to 40%, and a molar percentage of 5 ~30% alkaline earth ions and divalent metal ions, 5~25% copper ions with a molar ratio of 5 to 25%, wherein the molar ratio of copper ions and phosphorus ions can be between 0.1 and 0.5, and the fluoride ion is The ratio of mole percentages of both oxygen ions can be between 0.01 and 0.48.

After mixing and melting the above materials, these materials are cooled to obtain blue glass. Afterwards, the blue glass is crushed to obtain blue glass nanoparticles, wherein the particle size of each blue glass nanoparticle can be between 20 nanometers and 200 nanometers, preferably 100 nanometers. The method of crushing the blue glass can be wet or dry crushing method, or both crushing methods, and can be carried out using a ball mill and impact crushing device (nanomizer). In the process of pulverizing the blue glass, at least one liquid material such as water, alcohol, ketone, ether, ester and aldehyde can be used as the dispersion medium, wherein the mass percentage of the dispersion medium can be between 50% and 60%. After that, a centrifuge can be used to separate the dispersion medium from these blue glass nanoparticles. Then, washing, drying and dry crushing can be performed.

In addition, surfactants can also be used to disperse blue glass nanoparticles to weaken the agglomeration of blue glass nanoparticles, so that the average agglomerated particle size of infrared light absorbing particles 112 can be controlled to less than 80 nanometers to achieve good infrared Light absorption effect. The surfactant may be an anionic surfactant (such as at least one of a special polycarboxylic acid type polymer surfactant and an alkyl phosphate), and a nonionic surfactant (such as polyoxyethylene alkyl ether, polyoxyethylene alkane) Phenol ether, polyoxyethylene carboxylate and at least one sorbitan higher carboxylate), cationic surfactants (such as polyoxyalkylene alkylamine carboxylate, alkylamine and alkyl at least one salt ) Or amphoteric surfactants (such as high-grade alkyl beets).

After that, the blue glass nanoparticles and the binding material 111 are added to the solvent, and the blue glass nanoparticles are dissolved in the solvent to form a uniformly mixed solution, wherein the solvent is toluene or dimethylacetamide ( Dimethylacetamide, DMAC, alias N,N-dimethylacetamide). In the process of adding the blue glass nanoparticles and the binding material 111 to the solvent, at least one of the infrared light absorbing dye 113 and the ultraviolet light absorbing dye 114 may be added to the solvent to form the infrared light absorbing dye 113 and The light absorbing film 110 of at least one of the ultraviolet light absorbing dyes 114.

After that, the solution is cast on a smooth substrate, where the substrate is, for example, a glass plate. Then, the solution on the substrate is dried to form the light absorbing film 110, wherein the solution can be dried by means of over-drying or heating and drying. Next, the light absorbing film 110 is separated from the substrate to complete the manufacture of the light absorbing film 110, wherein the process of separating the light absorbing film 110 from the substrate can be performed in water. In addition, during the process of adding the blue glass nanoparticles and the binding material 111 to the solvent, at least one of the infrared light absorbing dye 113 and the ultraviolet light absorbing dye 114 may also be added to the solvent to form the infrared light absorbing dye and the ultraviolet light A light-absorbing film 110 that absorbs at least one of the dyes.

2 and 3 are schematic cross-sectional views of infrared light filters in other embodiments of the present invention, wherein the infrared light filters 200 and 300 shown in FIGS. 2 and 3 are similar to the infrared light filters in the foregoing embodiments片100. However, the infrared filters 200 and 300 are different from the infrared filter 100 in that the infrared filters 200 and 300 both include the second optical film 122 not disclosed in the foregoing embodiments.

The second optical film 122 may be an anti-reflection layer or an interference filter film, and may also be a multilayer film. However, the function of the second optical film 122 is different from the function of the first optical film 121. That is, when the second optical film 122 is an anti-reflection layer, the first optical film 121 is an interference filter film, wherein the second optical film 122 may also be a sub-wavelength structure. On the contrary, when the second optical film 122 is an interference filter film, the first optical film 121 is an anti-reflection layer.

The second optical film 122 may be formed on one side of the light absorption film 110. Taking FIG. 2 as an example, both the first optical film 121 and the second optical film 122 are formed on the same side of the light absorbing film 110, wherein the first optical film 121 may be located between the second optical film 122 and the light absorbing film 110. However, both the first optical film 121 and the second optical film 122 in FIG. 2 can be reversed. In other words, in other embodiments not shown, the second optical film 122 may be located between the first optical film 121 and the light absorption film 110. In addition, the light absorbing film 110 may also be located between the first optical film 121 and the second optical film 122, that is, the first optical film 121 and the second optical film 122 may be formed on opposite sides of the light absorbing film 110, as shown in FIG. 3 shown.

Although the present invention has been disclosed as above with examples, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention belongs can make some modifications and retouching without departing from the spirit and scope of the present invention. The scope of protection of invention shall be subject to the scope defined in the appended patent application.

100, 200, 300 ‧‧‧ infrared filter

110‧‧‧Light absorbing film

111‧‧‧Combined materials

112‧‧‧Infrared light absorbing particles

113‧‧‧Infrared absorption dye

114‧‧‧Ultraviolet absorption dye

121‧‧‧First optical film

122‧‧‧Second optical film

S1, S2, S3, S4, S5, S6‧‧‧‧curve

T1, T2‧‧‧thickness

FIG. 1A is a schematic cross-sectional view of an infrared light filter according to an embodiment of the invention. FIG. 1B is a schematic diagram of the transmission spectra of the light-absorbing film samples 1 to 6 in Table (1). 2 is a schematic cross-sectional view of an infrared light filter according to another embodiment of the present invention. 3 is a schematic cross-sectional view of an infrared light filter according to another embodiment of the present invention.

100‧‧‧Infrared filter

110‧‧‧Light absorbing film

111‧‧‧Combined materials

112‧‧‧Infrared light absorbing particles

113‧‧‧Infrared absorption dye

114‧‧‧Ultraviolet absorption dye

121‧‧‧First optical film

T1, T2‧‧‧thickness

Claims (19)

An infrared light filter includes: a light absorbing film, including: a binding material; and a plurality of infrared light absorbing particles distributed in the binding material, and the infrared light absorbing particles are all inorganic materials, of which The average agglomerated particle diameter of the infrared light absorbing particles is less than 80 nanometers; and a first optical film is formed on one side of the light absorbing film; wherein the thickness of the infrared light filter is between 10 microns and 500 microns, The infrared cut-off wavelength of the infrared filter is between 600 nm and 650 nm; the average transmittance of the light absorption film in the wavelength range of 700 nm to 725 nm is less than 1.8%, The infrared light filter has an average transmittance of less than 1% in the wavelength range of 700 nm to 1100 nm, and an average transmittance of more than 75% in the wavelength range of 430 nm to 580 nm. The infrared light filter according to claim 1, wherein the infrared light absorbing particles are amorphous particles. The infrared light filter according to claim 1, wherein the weight percentage between the infrared light absorbing particles and the bonding material is between 1% and 80%. The infrared light filter according to claim 1, wherein the infrared light absorbing particles are blue glass particles. The infrared light filter according to any one of claims 2 to 3, wherein the infrared light absorbing particles are blue glass particles. The infrared light filter according to claim 5, wherein the light absorption film An infrared light absorbing dye is also included, and the infrared light absorbing dye is distributed in the bonding material. The infrared light filter according to claim 5, wherein the light absorbing film further includes an ultraviolet light absorbing dye, and the ultraviolet light absorbing dye is distributed in the bonding material. The infrared light filter according to claim 5, wherein the light absorption film further includes an infrared light absorption dye and an ultraviolet light absorption dye, and the infrared light absorption dye and the ultraviolet light absorption dye are distributed on the Combined materials. The infrared light filter according to claim 5, wherein the bonding material includes an organic material. The infrared light filter according to claim 5, wherein the bonding material includes an inorganic material. The infrared light filter according to any one of claims 1 to 4, further comprising a second optical film formed on one side of the light absorption film. The infrared light filter according to claim 11, wherein the light absorption film is located between the first optical film and the second optical film. The infrared light filter according to any one of claims 1 to 4, wherein the melting points of the infrared light absorbing particles are less than 850°C. The infrared light filter according to any one of claims 1 to 4, wherein the bonding material includes polyimide or polycarbonate. The infrared light filter according to any one of claims 1 to 4, wherein an ultraviolet light cut-off wavelength of the infrared light filter is between 410 nm and 420 nm. The infrared light filter according to any one of claims 1 to 4, wherein the heat absorption rate of the light absorption film is less than or equal to 0.15%. The infrared light filter according to any one of claims 1 to 4, wherein the thermal softening temperature of the light absorption film is greater than or equal to 160°C. The infrared light filter according to any one of claims 1 to 4, wherein the bending strength of the light absorption film is between 90 MPa and 110 MPa. The infrared light filter according to any one of claims 1 to 4, wherein the average transmittance of the light absorption film in the wavelength range from 350 nm to 395 nm is less than 0.15%; the light absorption film is at The average transmittance in the wavelength range of 430 nm to 450 nm is greater than 78%.

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