CN201364391Y

CN201364391Y - Three-region high-efficiency anti-reflection film for visible region, 1.06Mu m and 8-12Mu m

Info

Publication number: CN201364391Y
Application number: CNU200820169338XU
Authority: CN
Inventors: 顾培夫; 艾曼灵; 张梅骄; 陈海星; 金波
Original assignee: Keting Optical Tech Co Ltd Hangzhou
Current assignee: Keting Optical Tech Co Ltd Hangzhou
Priority date: 2008-12-01
Filing date: 2008-12-01
Publication date: 2009-12-16
Anticipated expiration: 2018-12-01

Abstract

The utility model discloses a three-region high-efficiency anti-reflection film for visible region, 1.06Mu m and 8-12Mu m. A plurality of layers of low-refractive-index fluoride films and a plurality of layers of high-refractive-index sulphide films are alternately arranged on a high-refractive-index substrate to form the anti-reflection film. By choosing the thickness of each layer of film, the three-region high-efficiency anti-reflection film for visible region, 1.06Mu m and 8-12Mu m can be achieved. The average reflectivities of visible region (0.44-0.68Mu m), 1.06Mu m and 8-12Mu m are respectively reduced from about 20 percent, 17 percent and 14 percent before coating to 0.30 percent, 0.04 percent and 0.62 percent, and thereby an effective part is provided for multimode guidance.

Description

Visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film

Technical field

The utility model relates to highly effective antireflection film, relates in particular to a kind of visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film, belongs to highly effective antireflection film and makes the field.

Background technology

Antireflecting film is that a kind of film most widely used in the optical thin film is.From ultraviolet to infrared, from glass commonly used and plastic base to various crystal, from the physical vapor deposition to the chemical vapor deposition, from the monofilm to the multilayer film, from single incident angle to multiple angles of incidence, from single wavelength to the broadband and ultra broadband all carried out deep research the sixth of the twelve Earthly Branches, wherein greatly part becomes ripe the sixth of the twelve Earthly Branches, and can satisfy practical requirement the sixth of the twelve Earthly Branches.But relate to of the present utility modelly both realize wide band antireflective simultaneously, guarantee that again the efficient antireflecting film of optical maser wavelength 1.06 μ m system is badly in need of solving in visible range and far infrared region.Because wavelength width crosses far infrared from the visible range always, so all caused great difficulty for selection and design.

Improving constantly of optical thin film design and technology of preparing, make at present the conventional characteristics of antireflecting film the sixth of the twelve Earthly Branches that is used for visible region bandwidth B=λ max/ λ min=1.7 can be very near in addition reach the Design Theory value fully.But, because regular conventional antireflecting film generally is made up of quarter-wave layer and half wave layer, this becomes advantage because of it is easy to film thickness monitoring in the past, and today, this regular film system became shortcoming because of the film thickness monitoring precision reduces along with the film thickness monitoring development of technology; Secondly, regular film system is used 3-4 kind material always, find the stable material that can be applicable to the specific refractive index of different substrate again of refractive index still to acquire a certain degree of difficulty undoubtedly; At last, it is extremely difficult that this regular film system is used for some special antireflecting film designs.

Because relate to visible and two great spectral region of wavelength span of far infrared, substrate is often selected ZnS.ZnS is a kind of semiconductor material of high index of refraction, and the refractive index at its 0.633 μ m place in the visible range is 2.6, and the reflectivity that can calculate one surface is 19.7%; Refractive index at 1.06 μ m places is 2.4, and its surface reflectivity is 17.0%; And the refractive index at infrared 10 μ m places is 2.2, and surface reflectivity is 14.1%.After light is by several so big reflecting surfaces, not only greatly reduce the luminous energy that sees through, make the brightness of picture very low; And surface reflection comes back reflective and becomes parasitic light in optical system, causes the contrast of picture also very low, therefore must provide an antireflecting film efficiently.

Summary of the invention

The purpose of this utility model is in order to address the above problem, visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film on a kind of high index of refraction substrate to be provided.

As shown in Figure 1, antireflecting film is deposited on the semiconductor ZnS substrate of high index of refraction, membraneous material is selected ZnS and YbF3 for use, these two kinds of materials can match each other on mechanical property, can guarantee on visible range, 1.06 μ m and three wave bands of 8-12 μ m transparently on the optical property, and enough refringences arranged.The initial film system design of adopting can be expressed as following form: ZnS| (LH) ⁷L|Air, wherein L represents the YbF3 film of low-refraction, and H represents the ZnS film of high index of refraction, and centre wavelength is 600nm, and by optimizing, the thickness that obtains each tunic is listed in table 1.The optical thickness that low, high two kinds of refraction materials are listed by table 1 is deposited on the substrate successively, just can realize triband reflection preventing ability efficiently.

The quarter-wave optical thickness (QWOT) of each tunic of table 1. triband highly effective antireflection film

Material	Substrate	YbF3	ZnS	YbF3	ZnS	YbF3	ZnS	YbF3	ZnS
Material	Substrate	YbF3	ZnS	YbF3	ZnS	YbF3	ZnS	YbF3	ZnS	N (at 0.633 μ m)	2.6	1.52	2.32	1.52	2.32	1.52	2.32	1.52	2.32
QWOP		0.169	0.470	2.186	0.178	2.485	0.111	2.300	0.116	N (at 0.633 μ m)	2.6	1.52	2.32	1.52	2.32	1.52	2.32	1.52	2.32

Material	YbF3	ZnS	YbF3	ZnS	YbF3	ZnS	YbF3	Air
Material	YbF3	ZnS	YbF3	ZnS	YbF3	ZnS	YbF3	Air	N (at 0.633 μ m)	1.52	2.32	1.52	2.32	1.52	2.32	1.52	1.0
Geometric thickness/nm	2.510	0.184	1.247	0.103	0.801	0.402	1.124		N (at 0.633 μ m)	1.52	2.32	1.52	2.32	1.52	2.32	1.52	1.0

As can be seen from Table 1, the ZnS substrate is different with the refractive index of ZnS film, and this is because the low cause of the relatively large material of gather density of thin evaporated film; Secondly, each thicknesses of layers is non-regular thickness, and the thickness of YbF3 film is obviously greater than the thickness of ZnS film.

Above-mentioned design is 0.30% in the average residual reflectivity of visible range 0.44-0.68 μ m, and is 0.04% in the residual reflectivity of optical maser wavelength 1.06 μ m, and Fig. 2 represents the reflectance spectrum curve of these two wave bands.Because visible range 0.44-0.68 μ m and far infrared 8-12 μ m are separated by too big on the wavelength scale, be difficult to it is illustrated on the spectrogram, so the reflectance spectrum curve of far infrared atmospheric window 8-12 μ m is shown in Fig. 3, and on this wave band, residual reflectivity is 0.62%.Compare uncoated ZnS substrate surface, the reflectivity of three wave bands all significantly reduces behind the plated film.

Technical scheme: visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film, it comprises substrate 1, is positioned at multilayer low-refraction fluoride films and alternately stack formation of multilayer high index of refraction sulfide film on the substrate 1.

The utility model is compared with background technology, and the one, adopt two kinds of materials to design visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film on the high index of refraction substrate.Design shows, is under the given condition of total optical thickness and material refractive index at film, and to the antireflecting film of vertical incidence, the film structure of multiple material has more superiority unlike two kinds of materials; The 2nd, adopt two kinds of membraneous materials, as long as suitably select initial configuration,,, more can obtain three-wavelength reflection preventing ability efficiently though each tunic layer thickness right and wrong is regular by software optimization.

Description of drawings

Fig. 1 is the synoptic diagram of visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film.

Fig. 2 is the utility model reflectance spectrum curve of visible range and 1.06 μ m under 0 ° of incident angle in air.

Fig. 3 is the utility model reflectance spectrum curve of infrared region 8-12 μ m under 0 ° of incident angle in air.

Among the last figure: the YbF3 film 2 of substrate 1, low-refraction, the ZnS film 3 of high index of refraction, incident medium 4.

Embodiment

Embodiment 1: with reference to accompanying drawing 1～3.Visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film, it comprises substrate 1, and described substrate 1 is ZnS, and it is a kind of visible range, 1.06 μ m and 8-12 μ m material transparent, and incident medium 4 is an air.Be positioned at multilayer low-refraction fluoride films 2 on the substrate 1 and multilayer high index of refraction sulfide film 3 alternately stack constitute between----low-refraction fluoride films 2 and be equipped with high index of refraction sulfide film 3, the both sides outermost is respectively substrate 1 and air 4.The fluoride films 2 of described low-refraction is that the sulfide film 3 of YbF3 (2), high index of refraction is ZnS (3), by choosing the thickness of each tunic, just can realize visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film.When light in air during with 0 ° of angle incident, can be in the visible range, 1.06 μ m and three wave bands of 8-12 μ m realize high transmission simultaneously, the average reflectance of visible range 0.44-0.68 μ m, 1.06 μ m and each wave band of 8-12 μ m about 20% during by plated film not, 17% and 14% is reduced to 0.30% respectively, 0.04% and 0.62%, thus an active parts provided for multimode guidance.

As shown in Figure 1, a kind of visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film is characterized in that film system is made up of the alternate multi-layered film of low-refraction fluoride films on the semiconductor high index of refraction substrate and high index of refraction sulfide film.Substrate 1 is ZnS, and it is a kind of visible range, 1.06 μ m and 8-12 μ m material transparent.The fluoride films of low-refraction is YbF3 2, and the sulfide film of high index of refraction is ZnS 3.Incident medium 4 is an air.

On the ZnS substrate, plate YbF3 and ZnS film successively, control the thickness of each tunic, after having plated 15 tunics, can realize visible range of the present utility model, 1.06 μ m and 8-12 μ m triband highly effective antireflection film, when light in air during with 0 ° of angle incident, can be in the visible range, 1.06 μ m and three wave bands of 8-12 μ m are realized high transmission simultaneously, visible range 0.44-0.68 μ m, 1.06 the average reflectance of μ m and each wave band of 8-12 μ m about 20% during by plated film not, 17% and 14% is reduced to 0.30% respectively, 0.04% and 0.62%, thus an active parts provided for multimode guidance.

What need understand is: though the foregoing description is to the utility model detailed text description of contrasting; but these text descriptions; just the simple text of the utility model mentality of designing is described; rather than to the restriction of the utility model mentality of designing; any combination, increase or modification that does not exceed the utility model mentality of designing all falls in the protection domain of the present utility model.

Claims

1, a kind of visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film, it comprises substrate, it is characterized in that: be positioned at multilayer low-refraction fluoride films and alternately stack formation of multilayer high index of refraction sulfide film on the substrate.

2, visible range according to claim 1,1.06 μ m and 8-12 μ m triband highly effective antireflection film, it is characterized in that: the fluoride films of described low-refraction is that the sulfide film of YbF3, high index of refraction is ZnS.

3, visible range according to claim 1,1.06 μ m and 8-12 μ m triband highly effective antireflection film, it is characterized in that: described substrate is ZnS, and it is a kind of visible range, 1.06 μ m and 8-12 μ m material transparent, and the incident medium is an air.

4, visible range according to claim 1 and 2,1.06 μ m and 8-12 μ m triband highly effective antireflection film, it is characterized in that: be equipped with the high index of refraction sulfide film between the low-refraction fluoride films, the both sides outermost is respectively substrate and air.

5, visible range according to claim 1,1.06 μ m and 8-12 μ m triband highly effective antireflection film is characterized in that: by choosing the thickness of each tunic, just can realize visible range, 1.06 μ m and 8-12 μ m triband highly effective antireflection film.