CN100430757C - Bandpass filter capable of reducing coating layer number - Google Patents

Abstract

The invention discloses a band-pass filter capable of reducing the number of coating layers, which comprises: a substrate, a stack of substrates and a display (LH multiplied by LH)^mThe film structure of the invention comprises a main film, a first matching film and a second matching film, wherein the main film is sandwiched between the main film and a substrate, the average transmittance in a first correction waveband of the first matching film is more than 85%, and the second matching film is stacked on the main film, and the average transmittance in a second correction waveband of the second matching film is more than 95%. The average penetration rate of the main film in the first waveband is more than 80 percent; the average penetration rate in the second and third wave bands is between 40% and 60%; the average penetration rate in the fourth and fifth wave bands is less than 1%, x is 2n, n is a positive integer, and m is less than or equal to 6. The second band is between the first and fourth bands, the third band is between the first and fifth bands, and the second and third bandsThe wavelengths are smaller than the first band and larger than the first band, respectively. The first band is within the first modified band and the second modified band is within the first band.

Description

Bandpass Filters to Reduce the Number of Coating Layers

technical field

The invention relates to a band pass filter, in particular to a band pass filter which can reduce the number of coating layers.

Background technique

At present, the film layer structure of the band-pass filter can be divided into two common ways: one is double-sided optical coating, taking the visible light band-pass filter as an example, which is divided into two planes on a glass substrate. Coated with an ultraviolet cut (UV cut) coating and a far infrared cut (IR cut) coating; the other is a single-sided optical coating, taking the green bandpass filter as an example, it is on a glass substrate Dozens of high and low value refractive layers of equal thickness are plated on one of the planes.

Generally, the band-pass filter composed of double-sided optical coating not only affects the final transmittance due to the total film thickness accumulated on both sides is too thick, but also must consider the single-sided optical spectroscopic characteristics and double-sided synthesis effect. Therefore, it is more complicated when designing the film structure.

The band-pass filter with single-sided optical coating can be referred to FIG. 1. A traditional band-pass filter 1 includes: a substrate 11, a first film stack 12 stacked along a direction X, and a second film stack 13 and a third membrane stack 14 .

The first film stack 12 is stacked with a film structure of (0.7332H/0.7332L) ¹⁰ along the direction X; the second film stack 13 is stacked with a film structure of (1.308H/1.308L) ¹⁰ along the direction X. Film layer structure; the third film stack 14 is stacked with a film layer structure of (1.4H/1.4L) ¹⁰ along the direction X; wherein, a central wavelength (λ ₀ ) of the bandpass filter 1 is 465nm , H and L are a high refraction layer and a low refraction layer equal to λ ₀ /4.

From the foregoing description, the total film structure of the traditional bandpass filter 1 [that is, (0.7332H/0.7332L) ¹⁰ /(1.308H/1.308L) ¹⁰ /(1.4H/1.4L) ¹⁰ ] The thickness is described below:

λ ₀ =465, $h=L=\frac{{\mathrm{\λ}}_0}{4}=\frac{465}{4},$ $h+L=\frac{{\mathrm{\λ}}_0}{2}=\frac{465}{2}$

$<span\; class="notranslate">\; =</span><span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; 7.332</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 13.08</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 14</span>}<span\; class="notranslate">\; ]</span>\frac{\mathrm{<span\; class="notranslate">\; 465</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 8002.65</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; nm</span>}<span\; class="notranslate">\; )</span>$

In addition, referring to FIG. 2 , the transmittance spectrograms of the membrane stacks 12, 13, and 14 of the bandpass filter 1 show that the efficacy of the first membrane stack 12 lies in the band with a cutoff wavelength greater than 500nm. The effect of the second film stack 13 is to increase the transmittance of the wavelength band less than 500nm, and the effect of the third film stack 14 is to cut off the wave band with a wavelength less than 400nm. To form a bandpass filter 1 capable of filtering wavelengths between 400nm and 500nm.

Referring to Fig. 3, it is shown by the transmittance spectrogram of this band-pass filter 1 that the transmittance curve after the stack 12, 13, 14 is superimposed is serious jitter (ripper), and due to the The total film thickness of the bandpass filter 1 is as high as about 8000nm, which can easily cause the scattering phenomenon and cause the average transmittance to be unable to be maintained above 80%. Therefore, not only the production cost of the coating is increased, but also the The optical separation of the bandpass filter 1.

Therefore, designing a film layer structure that can suppress the white fog phenomenon to achieve good optical spectroscopic characteristics and effectively reduce the production cost of the coating is the current direction of efforts for those in the field of developing bandpass filters.

Contents of the invention

The purpose of the present invention is to provide a band-pass filter that can reduce the number of coating layers, and it is a film layer structure that can suppress the white fog phenomenon to achieve good optical spectral characteristics, and effectively reduce the coating production cost. Bandpass filter with reduced number of coating layers.

The present invention is a band-pass filter capable of reducing the number of coating layers, comprising: a base material, a main film stacked on the base material, a first matching film sandwiched between the main film and the base material film, and a second matching film stacked on the main film.

The main film is sequentially stacked from the base material to a stacking direction away from the base material and has a film layer structure of (LHxLH) ^m . The average transmittance of the main film in a first wave band is greater than 80%, the average transmittance in a second wave band and a third wave band is respectively between 40% and 60%, and in a fourth wave band and a The average transmittance of the fifth band is less than 1% respectively; wherein, H and L are a high refraction material and a low refraction material respectively, x is equal to 2n, n is a positive integer, m≤6. the second waveband is between the first and fourth wavebands, the third waveband is between the first and fifth wavebands, and the wavelength of the second waveband is smaller than the wavelength of the first waveband, The wavelength of the third waveband is greater than the wavelength of the first waveband.

The first matching film is sequentially stacked with a film layer structure of 2HLH2LH along the stacking direction, the average transmittance in a first correction waveband is greater than 85%, and the first waveband is between the first within the correction band.

The second matching film is sequentially stacked with a layer structure of L2HL2HL along the stacking direction, and the average transmittance of a second correction waveband in the first waveband is greater than 95%.

Wherein, H and L are respectively the high refraction material and the low refraction material with a thickness equal to λ ₀ /4, and λ ₀ is a wavelength between 380nm˜1100nm.

The efficacy of the present invention lies in that it has a film layer structure that can suppress the white fog phenomenon to achieve good optical spectroscopic characteristics, and effectively reduces the production cost of the coating film.

Description of drawings

Fig. 1 is a schematic sectional view illustrating a conventional bandpass filter;

Fig. 2 is a first, a second and a third film stack of this traditional bandpass filter before the transmittance spectrogram;

Fig. 3 is the transmittance spectrogram after the first, second and third film stacks of this traditional bandpass filter are added;

Fig. 4 is a schematic sectional view illustrating a first preferred embodiment of the band-pass filter of the present invention that can reduce the number of coating layers;

Fig. 5 is the transmittance spectrogram of a main film of this first preferred embodiment;

Fig. 6 is the transmittance spectrogram of a first matching film of the first preferred embodiment;

Fig. 7 is the transmittance spectrogram after the main film and the first matching film of the first preferred embodiment are superimposed;

Fig. 8 is a transmittance spectrogram of a second matching film of the first preferred embodiment;

Fig. 9 is a spectrogram of transmittance after superimposing the main film and the second matching film of the first preferred embodiment;

Fig. 10 is the transmittance spectrogram after the main film, the first and the second matching film are stacked in the first preferred embodiment;

Fig. 11 is a transmittance spectrogram of a main film of a second preferred embodiment;

Fig. 12 is the transmittance spectrogram of the main film, a first and a second matching film stacked in the second preferred embodiment;

Fig. 13 is a transmittance spectrogram of a main film of a third preferred embodiment;

Fig. 14 is the transmittance spectrogram of the main film, a first and a second matching film stacked in the third preferred embodiment;

Fig. 15 is a transmittance spectrogram of a main film of a fourth preferred embodiment;

Fig. 16 is a transmittance spectrogram of a first matching film of the fourth preferred embodiment;

Fig. 17 is a transmittance spectrogram of a second matching film of the fourth preferred embodiment;

Fig. 18 is the transmittance spectrogram of the main film, the first and the second matching film stacked in the fourth preferred embodiment;

Fig. 19 is a transmittance spectrogram of a main film of a fifth preferred embodiment;

Fig. 20 is a transmittance spectrogram of a first matching film of the fifth preferred embodiment;

Fig. 21 is the transmittance spectrogram of a second matching film of the fifth preferred embodiment:

Fig. 22 is a spectrogram of the transmittance after the main film, the first and the second matching films are superimposed in the fifth preferred embodiment.

Detailed ways

The bandpass filter that can reduce the number of coating layers of the present invention will be described in detail below through specific embodiments and accompanying drawings.

Referring to Fig. 4, a first preferred embodiment of the bandpass filter which can reduce the number of coating layers of the present invention comprises: a substrate 2, a main film 3 stacked on the substrate 2, a sandwiched A first matching film 4 between the main film 3 and the substrate 2 , and a second matching film 5 stacked on the main film 3 .

The main film 3 is sequentially stacked from the base material 2 in a stacking direction Y away from the base material 2 and has a film layer structure of (LH×LH) ^m . The average transmittance of the main film 3 in a first wave band is greater than 80%, the average transmittance in a second wave band and a third wave band are respectively between 40% and 60%, and in a fourth wave band and - the average penetration rate of the fifth band is less than 1% respectively; wherein, x is equal to 2n, n is a positive integer, and m≤6. the second waveband is between the first and fourth wavebands, the third waveband is between the first and fifth wavebands, and the wavelength of the second waveband is smaller than the wavelength of the first waveband, The wavelength of the third waveband is greater than the wavelength of the first waveband.

The first matching film 4 is sequentially stacked with a film structure of 2HLH2LH along the stacking direction Y, the average transmittance in a first correction waveband is greater than 85%, and the first waveband is between the within the first correction band.

The second matching film 5 is sequentially stacked with a layer structure of L2HL2HL along the stacking direction Y, and the average transmittance of a second correction waveband within the first waveband is greater than 95%.

In the bandpass filter capable of reducing the number of coating layers of the present invention, H and L are respectively a high-refraction material and a low-refraction material with a thickness equal to λ ₀ /4, and λ ₀ is a wavelength between 380nm and 1100nm. The λ ₀ applicable to the first preferred embodiment of the present invention is a wavelength between 445nm and 485nm, and 1≤n≤3; in addition, the refractive index (refractive index) suitable for the high refractive material of the present invention is between 2.1-2.5, and the low-refractive material has a refractive index between 1.3-1.5.

In the first preferred embodiment, n=1 (that is, x=2), m=6, λ ₀ is a wavelength of 465 nm; the high refractive material is titanium dioxide (TiO ₂ ), and the low refractive material is di Silicon oxide (SiO ₂ ).

To sum up the foregoing, in the first preferred embodiment of the present invention, the film layer structure of the substrate 2, the first matching film 4, the main film 3 and the second matching film 5 along the stacking direction Y is as follows: Material/2HLH2LH/(LH2LH) ⁶ /L2HL2HL/air.

Referring to Fig. 5, the transmittance spectrogram of the main film 3 of the first preferred embodiment shows that under the condition that λ ₀ is a wavelength of 465nm, the first band average transmittance between 440nm～500nm is greater than 90%; the average transmittance of the second wave band of 428±5nm and the third wave band of 515±5nm is between 40% and 60%; The average transmittance of the fifth wave band between 530nm and 600nm is less than 1%.

Referring to Fig. 6, the transmittance spectrogram of the first matching film 4 of the first preferred embodiment shows that under the condition that λ ₀ is a wavelength of 465nm, the first correction waveband between 440nm and 500nm The average penetration rate is greater than 95%. In addition, referring to FIG. 7 , the transmittance spectrogram after superimposing the main film 3 and the first matching film 4 of the first preferred embodiment shows that the main function of the first matching film 3 is to correct the The average transmittance of the first band between 500nm.

Referring to Fig. 8, the transmittance spectrogram of the second matching film 5 of the first preferred embodiment shows that under the condition that λ ₀ is a wavelength of 465nm, the second correction waveband between 460nm and 480nm The average penetration rate is greater than 95%. In addition, referring to FIG. 9 , the transmittance spectrogram after superposition of the main film 3 and the second matching film 5 of the first preferred embodiment shows that the main function of the second matching film 5 is to correct the The average penetration between the second correction bands.

Referring to Fig. 10, the transmittance spectrogram after superposition of the main film 3, the first matching film 4 and the second matching film 5 of the first preferred embodiment shows that the first preferred embodiment of the present invention can reduce the coating The average transmittance of the band-pass filter of the number of layers in the first waveband (that is, the wavelength between 440nm and 500nm) is greater than 95%, and the transmittance in the second and third wavebands The steepness of the curve effectively filters the wavelengths of this first band.

In addition, the total film thickness of the film structure [that is, 2HLH2LH/(LH2LH) ⁶ /L2HL2HL] of the first preferred embodiment of the present invention is as follows:

λ ₀ =465, $h=L=\frac{{\mathrm{\&lambda;}}_0}{4}=\frac{465}{4}$

$<span\; class="notranslate">\; =</span><span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; ]</span>\frac{\mathrm{<span\; class="notranslate">\; 465</span>}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 5115</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; nm</span>}<span\; class="notranslate">\; )</span>$

Compared with the traditional bandpass filter 1, the total film thickness of the first preferred embodiment of the present invention is significantly reduced by about 3000 nm. Therefore, the white fog phenomenon can be effectively suppressed and the transmittance can be increased. In addition, compared with the traditional bandpass filter 1, each film layer of the present invention is designed to be of equal thickness, so it is beneficial to process monitoring during the coating process.

A second preferred embodiment of the band-pass filter that can reduce the number of coating layers of the present invention is substantially the same as the first preferred embodiment, and its difference is only n=2 (that is, x=4 ).

Therefore, in the second preferred embodiment of the present invention, the film layer structure of the substrate 2, the first matching film 4, the main film 3 and the second matching film 5 along the stacking direction Y is as follows: the substrate /2HLH2LH/(LH4LH) ⁶ /L2HL2HL/air.

Referring to Fig. 11, the transmittance spectrogram of the main film 3 of this second preferred embodiment shows that this _second preferred embodiment is between 445nm～ The average transmittance of the first band between 490nm and 490nm is greater than 80%; the average transmittance of the second band of 439±5nm and the third band of 496±5nm is between 40% and 60%; The average transmittance of the fourth waveband between 400nm-430nm and the fifth waveband between 510nm-580nm is less than 1%. In addition, referring to FIG. 6 again, the average transmittance of the first matching film 4 in the first correction wavelength band between 440nm and 500nm is greater than 95%; and as shown in FIG. 8, the second matching film 5 is between The average transmittance of the second correction wavelength band between 460nm-480nm is greater than 95%.

Referring to Fig. 12, the transmittance spectrogram of the superposition of the main film 3, the first matching film 4 and the second matching film 5 of the second preferred embodiment shows that the second preferred embodiment of the present invention can reduce the coating The average transmittance of the bandpass filter of the number of layers in the first waveband (that is, the wavelength between 445nm and 490nm) is greater than 90%, and the transmittance in the second and third wavebands The steepness of the curve is high, so the wavelengths of this first band can be effectively filtered.

In addition, the total film thickness of the film structure [that is, 2HLH2LH/(LH4LH) ⁶ /L2HL2HL] of the second preferred embodiment of the present invention is as follows:

λ ₀ =465, $h=L=\frac{{\mathrm{\&lambda;}}_0}{4}=\frac{465}{4}$

$<span\; class="notranslate">\; =</span><span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; ]</span>\frac{\mathrm{<span\; class="notranslate">\; 465</span>}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 6510</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; nm</span>}<span\; class="notranslate">\; )</span>$

Compared with the traditional bandpass filter 1, the total film thickness of the second preferred embodiment of the present invention is significantly reduced by about 1500nm. Therefore, the white fog phenomenon can also be effectively suppressed to increase the transmittance.

A third preferred embodiment of the band-pass filter that can reduce the number of coating layers of the present invention is substantially the same as the first preferred embodiment, and its difference is only n=3 (that is, x=6 ).

Therefore, in the third preferred embodiment of the present invention, the film layer structure of the substrate 2, the first matching film 4, the main film 3 and the second matching film 5 along the stacking direction Y is as follows: the substrate /2HLH2LH/(LH6LH) ⁶ /L2HL2HL/air.

Referring to Fig. 13, it is shown by the transmittance spectrogram of the main film 3 of this third preferred embodiment, that this _third preferred embodiment is between 450nm～ The average transmittance of the first band between 480nm and 480nm is greater than 80%; the average transmittance of the second band of 444±5nm and the third band of 488±5nm is between 40% and 60%; The average transmittance of the fourth waveband between 400nm-440nm and the fifth waveband between 500nm-550nm is less than 1%. In addition, referring to FIG. 6 again, the average transmittance of the first matching film 4 in the first correction wavelength band between 440nm and 500nm is greater than 95%; and as shown in FIG. 8, the second matching film 5 is between The average transmittance of the second correction wavelength band between 460nm-480nm is greater than 95%.

Referring to FIG. 14 , the transmittance spectrogram after superposition of the main film 3, the first matching film 4 and the second matching film 5 of the third preferred embodiment shows that the third preferred embodiment of the present invention can reduce the coating The average transmittance of the bandpass filter of the number of layers in the first waveband (that is, the wavelength between 450nm and 485nm) is greater than 88%, and the transmittance in the second and third wavebands The steepness of the curve effectively filters the wavelengths of this first band.

Also, the total film thickness of the film layer structure [that is, 2HLH2LH/(LH6LH) ⁶ /L2HL2HL] of the third preferred embodiment of the present invention is as follows:

λ ₀ =465, $h=L=\frac{{\mathrm{\&lambda;}}_0}{4}=\frac{465}{4}$

$<span\; class="notranslate">\; =</span><span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 9</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; ]</span>\frac{\mathrm{<span\; class="notranslate">\; 465</span>}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 7905</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; nm</span>}<span\; class="notranslate">\; )</span>$

Compared with the traditional bandpass filter 1, the total film thickness of the third preferred embodiment of the present invention is reduced by about 100nm. Therefore, if the total film thickness of the third preferred embodiment is to be reduced, the main film can also be reduced. The m value of 3, thereby suppressing the white fog phenomenon and achieving the effect of increasing the penetration rate.

A fourth preferred embodiment of the band-pass filter of the present invention that can reduce the number of coating layers is substantially the same as the first preferred embodiment, and the only difference lies in the wavelength of _λ0 . The λ ₀ suitable for the fourth preferred embodiment of the present invention is a wavelength between 385nm and 420nm. In this fourth preferred embodiment, λ ₀ is a wavelength of 400 nm.

Referring to FIG. 15 , the transmittance spectrum of the main film 3 of the fourth preferred embodiment shows that the fourth preferred embodiment has a transmittance between 382nm and 430nm under the condition that λ ₀ is a wavelength of 400nm. The average transmittance of the first band is greater than 80%; the average transmittance of the second band of 376±5nm and the third band of 437±5nm is between 40% and 60%; and between 350nm and 370nm The average transmittance of the fourth waveband and the fifth waveband between 450nm and 500nm is less than 1%.

In addition, referring to FIG. 16 , the average transmittance of the first matching film 4 in the fourth preferred embodiment of the present invention in the first correction wavelength band between 380nm and 430nm is greater than 85%; and, as shown in FIG. 17 According to the fourth preferred embodiment of the present invention, the average transmittance of the second matching film 5 in the second correction wavelength band between 395nm and 405nm is greater than 95%.

Referring to FIG. 18 , the transmittance spectrogram after superposition of the main film 3, the first matching film 4 and the second matching film 5 of the fourth preferred embodiment shows that the fourth preferred embodiment of the present invention can reduce the coating The average transmittance of the band-pass filter of the number of layers in the first waveband (that is, the wavelength between 382nm and 430nm) is greater than 95%, and the transmittance in the second and third wavebands The steepness of the curve effectively filters the wavelengths of this first band.

A fifth preferred embodiment of the band-pass filter of the present invention that can reduce the number of coating layers is substantially the same as the first preferred embodiment, and the only difference lies in the wavelength of _λ0 . The λ ₀ suitable for the fifth preferred embodiment of the present invention is a wavelength between 860 nm˜940 nm. In this fifth preferred embodiment, λ ₀ is a wavelength of 900 nm.

Referring to Fig. 19, it is shown by the transmittance spectrogram of the main film 3 of the fifth preferred embodiment that under the condition that λ ₀ of the fifth preferred embodiment is a wavelength of 900 nm, the transmittance between 830nm and 980nm The average transmittance of the first band is greater than 80%; the average transmittance of the second band of 812±5nm and the third band of 1012±5nm is between 40% and 60%; and between 700nm and 790nm The average transmittance of the fourth waveband and the fifth waveband between 1040nm and 1200nm is less than 1%.

In addition, referring to FIG. 20, the average transmittance of the first matching film 4 in the fifth preferred embodiment of the present invention in the first correction wavelength band between 830nm and 980nm is greater than 85%; and as shown in FIG. 21, The average transmittance of the second matching film 5 of the fifth preferred embodiment of the present invention in the second correction wavelength band between 885nm and 915nm is greater than 95%.

Referring to Fig. 22, the transmittance spectrogram after superposition of the main film 3, the first matching film 4 and the second matching film 5 of the fifth preferred embodiment shows that the fifth preferred embodiment of the present invention can reduce the coating The average transmittance of the band-pass filter of the number of layers in the first waveband (that is, the wavelength between 830nm and 980nm) is greater than 95%, and the transmittance in the second and third wavebands The steepness of the curve is high, so the wavelengths of this first band can be effectively filtered.

The detailed film structure of the preferred embodiment of the present invention [that is, 2HLH2LH/(LHxLH) ^m /L2HL2HL], λ ₀ value, total film thickness and the transmittance of each band are arranged in the following table 1.

Table 1.

Compared with the traditional band-pass filter 1, the film structure designed by the preferred embodiment of the present invention not only has a good transmittance curve steepness, but also the filter bands corresponding to each preferred embodiment can be Reach more than 85% transmittance, in addition, the final total film thickness of this first, second, third preferred embodiment of the present invention is also lower than this traditional band-pass filter 1, therefore, can effectively reduce the production of coating film cost and suppress the generation of white fog phenomenon.

To sum up the above, the present invention can reduce the number of coating layers of the bandpass filter, has a film layer structure that can suppress the white fog phenomenon to achieve good optical spectral characteristics, and effectively reduces the production cost of the coating, and can indeed achieve the purpose of the present invention.

Claims (11)

1. the bandpass filter of a piece capable of reducing coating-plated layers is characterized in that, this bandpass filter comprises:

One base material;

One is stacked and placed on the main film of this base material, is stacked with one by this base material in regular turn to the stacked direction away from this base material and is (LHxLH) ^mFilm layer structure, this main film in the average penetration rate of one first wave band greater than 80%, average penetration rate in one second wave band and a triband is respectively between 40%～60%, average penetration rate in one the 4th wave band and one the 5th wave band is respectively less than 1%, wherein, H and L are respectively a high-refraction material and a low refractive material, x equals 2n, n is a positive integer, m≤6, this second wave band are between this first and the 4th wave band, and this triband is between this first and the 5th wave band, and the wavelength of this second wave band is the wavelength less than this first wave band, and the wavelength of this triband is the wavelength greater than this first wave band; One be folded between this main film and this base material and along this stacked direction be stacked with in regular turn one be 2HLH2LH film layer structure first mate film, in the one first average penetration rate of revising in the wave band is greater than 85%, and this first wave band is in this first correction wavelength band; And

One be stacked and placed on this main film and along this stacked direction be stacked with in regular turn one be L2HL2HL film layer structure second the coupling film, in this first wave band one second the correction wave band the average penetration rate be greater than 95%;

Wherein, the thickness of H and L equals λ respectively ₀This high-refraction material of/4 reaches and should hang down refractive material, λ ₀Be wavelength between 380nm～1100nm.

2. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 1 is characterized in that: 1≤n≤3, and λ ₀Be wavelength between 445nm～485nm.

3. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 2 is characterized in that: n=1, m=6, λ ₀Wavelength for 465nm, this first wave band is between 440nm～500nm, this second and third wave band is respectively 428 ± 5nm and 515 ± 5nm, the the 4th and the 5th wave band is respectively between between 400nm～420nm and between 530nm～600nm, and this first correction wave band and this second correction wave band are respectively between between 440nm～500nm and between 460nm～480nm.

4. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 2 is characterized in that: n=2, m=6, λ ₀Wavelength for 465nm, this first wave band is between 445nm～490nm, this second and third wave band is respectively 439 ± 5nm and 496 ± 5nm, the the 4th and the 5th wave band is respectively between between 400nm～430nm and between 510nm～580nm, and this first correction wave band and this second correction wave band are respectively between between 440nm～500nm and between 460nm～480nm.

5. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 2 is characterized in that: n=3, m=6, λ ₀Wavelength for 465nm, this first wave band is between 450nm～480nm, this second and third wave band is respectively 444 ± 5nm and 488 ± 5nm, the the 4th and the 5th wave band is respectively between between 400nm～440nm and between 500nm～550nm, and this first correction wave band and this second correction wave band are respectively between between 440nm～500nm and between 460nm～480nm.

6. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 1 is characterized in that: λ ₀Be wavelength between 385nm～420nm.

7. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 6 is characterized in that: wherein, and n=1, m=6, λ ₀Wavelength for 400nm, this first wave band is between 382nm～430nm, this second and third wave band is respectively 376 ± 5nm and 437 ± 5nm, the the 4th and the 5th wave band is respectively between between 350nm～370nm and between 450nm～500nm, and this first correction wave band and this second correction wave band are respectively between between 380nm～430nm and between 395nm～405nm.

8. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 1 is characterized in that: λ ₀Be wavelength between 860nm～940nm.

9. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 8 is characterized in that: n=1, m=6, λ ₀Wavelength for 900nm, this first wave band is between 830nm～980nm, this second and third wave band is respectively 812 ± 5nm and 1012 ± 5nm, the the 4th and the 5th wave band is respectively between between 700nm～790nm and between 1040nm～1200nm, and this first correction wave band and this second correction wave band are respectively between between 830nm～980nm and between 885nm～915nm.

10. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 1, it is characterized in that: the refractive index of this high-refraction material is between 2.1 to 2.5, the refractive index of this low refractive material is between 1.3 to 1.5.

11. the bandpass filter of piece capable of reducing coating-plated layers as claimed in claim 10 is characterized in that: this high-refraction material is a titania, and this low refractive material is a silicon dioxide.

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