JP5279428B2

JP5279428B2 - Wide area heat ray cut filter

Info

Publication number: JP5279428B2
Application number: JP2008244790A
Authority: JP
Inventors: 晋治野口
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2008-09-24
Filing date: 2008-09-24
Publication date: 2013-09-04
Anticipated expiration: 2028-09-24
Also published as: JP2010078714A

Abstract

<P>PROBLEM TO BE SOLVED: To improve the transmittance of visible light, to cut a wide-area heat ray, and to prevent the deterioration of a heat ray cutting effect even in continuous use at high temperatures. <P>SOLUTION: This wide area heat ray cut filter 1 includes an optical multilayer film 8 on a transparent substrate 7. The optical multilayer film 8 is formed by alternately stacking high refractive index material layers 9 and low refractive index material layers 10, and has a first reflection section 11 for reflecting the heat ray of a wavelength of about 1,000-2,000 nm and a second reflection section 12 for reflecting the heat ray of a wavelength of about 800-1,300 nm. The first reflection section 11 has a first structure 13 where a thin high refractive index material layer 9, a thin low refractive index material layer 10, and a thick high refractive index material layer 9 are sequentially stacked, and a second structure 14 where a thin low refractive index material layer 10, a thin high refractive index material layer 9, and a thick low refractive index material layer 10 are sequentially stacked. The first structure 13 and the second structure 14 are alternately stacked. In the cut filter 1, the transmittance for the visible light and the heat ray cutting effect are improved, and the heat ray cutting effect is not deteriorated even in continuous use at high temperatures. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は、照明光源から発生する不要な熱線、すなわち熱線波長域の光を遮蔽する広域熱線カットフィルタに関する。 The present invention relates to a wide-area heat ray cut filter that shields unnecessary heat rays generated from an illumination light source, that is, light in a heat ray wavelength region.

店舗や舞台で使用されるスポットライト照明器具及びプロジェクタの光源は、演色性が良く、点灯・消灯の切り替えが容易なハロゲンランプが一般的に使われる。このようなハロゲンランプの放射スペクトルを図６に示す。ハロゲンランプから放射される可視光の量に比べて、放射される熱線（赤外線）の量は非常に多い。そのため、例えば、ハロゲンランプを備えるスポットライト照明器具を使用したとき、被照射物は明るく照らされると同時に、大量の熱線が放射されることになる。そこで、熱線吸収ガラス、熱線反射フィルタ等をハロゲンランプの光出射口近傍に配置することによって、ハロゲンランプから放射される不要な熱線をカットしている。 As a light source of a spotlight illuminator and a projector used in a store or a stage, a halogen lamp which has a good color rendering property and can be easily switched on / off is generally used. The radiation spectrum of such a halogen lamp is shown in FIG. The amount of heat rays (infrared rays) emitted is much larger than the amount of visible light emitted from the halogen lamp. Therefore, for example, when a spotlight illuminator equipped with a halogen lamp is used, the irradiated object is brightly illuminated and a large amount of heat rays are emitted. Therefore, unnecessary heat rays radiated from the halogen lamp are cut by arranging a heat ray absorbing glass, a heat ray reflection filter, and the like in the vicinity of the light outlet of the halogen lamp.

熱線をカットするために用いられる熱線吸収ガラスは、微量のコバルト、鉄、セレン等の金属が混入されたガラスであり、熱線を吸収することができる。しかしながら、熱線吸収ガラスは、高出力の光源であるハロゲンランプから放射される熱線を多量に吸収することで破損してしまうため、２００℃程度までが使用限界温度である。また、熱線吸収ガラスは可視光の透過率が良くない。 The heat ray absorbing glass used for cutting the heat ray is a glass mixed with a trace amount of metal such as cobalt, iron, selenium and the like, and can absorb the heat ray. However, the heat-absorbing glass is broken by absorbing a large amount of heat rays emitted from a halogen lamp, which is a high-power light source. Further, the heat ray absorbing glass does not have a good visible light transmittance.

熱線をカットするために用いられる熱線反射フィルタは、ガラスや水晶等の透明基板上に光学多層膜が形成される（例えば、特許文献１及び特許文献２参照）。普通の光学多層膜を備える熱線反射フィルタは、熱線をカットする領域が狭いため、７８０〜１２００ｎｍの波長の熱線をカットできても、１２００ｎｍより長い波長の熱線をカットできない。そこで、光学多層膜を形成する高屈折率材料層と低屈折率材料層の光学膜厚は、１２００ｎｍより長い波長の熱線をカットするために、設計波長をλとしたとき、ｎｄ＝λ／４（ｎ：屈折率、ｄ：膜厚）の構成となるように設計されることが考えられる。しかしながら、上記のように設計された光学多層膜を備える熱線反射フィルタは、可視光領域の透過スペクトルにディンプルが発生するために、透過光に色むらが発生し、可視光の透過率が低下する。 In a heat ray reflective filter used for cutting heat rays, an optical multilayer film is formed on a transparent substrate such as glass or quartz (see, for example, Patent Literature 1 and Patent Literature 2). A heat ray reflective filter provided with an ordinary optical multilayer film has a narrow area for cutting heat rays, so even if it can cut heat rays with a wavelength of 780 to 1200 nm, it cannot cut heat rays with a wavelength longer than 1200 nm. Therefore, the optical film thickness of the high refractive index material layer and the low refractive index material layer forming the optical multilayer film is such that nd = λ / 4 when the design wavelength is λ in order to cut heat rays having a wavelength longer than 1200 nm. It may be designed to have a configuration of (n: refractive index, d: film thickness). However, in the heat ray reflective filter including the optical multilayer film designed as described above, dimples are generated in the transmission spectrum in the visible light region, so that the color of the transmitted light is uneven and the visible light transmittance is reduced. .

カットできる熱線領域を広くするための別の手段として、カットできる熱線領域の異なる複数個の熱線反射フィルタを使用することが考えられるが、部品点数が増加して高価となる。また、さらに別の手段として、熱線吸収ガラスと熱線反射フィルタとを組み合わせることが考えられるが、この組み合わせでは、広域の熱線が綺麗にカットされず、可視光の透過特性が悪く、部品点数が増加して高価となる。 As another means for widening the heat ray region that can be cut, it is conceivable to use a plurality of heat ray reflection filters having different heat ray regions that can be cut. However, the number of parts increases and the cost increases. In addition, as another means, it is conceivable to combine a heat ray absorbing glass and a heat ray reflection filter, but in this combination, a wide range of heat rays is not cut cleanly, the visible light transmission characteristics are poor, and the number of parts increases. And expensive.

そこで、透明ガラス基板上に１０層以上が積層された光学多層薄膜に、Ｉｎ_２Ｏ_３及びＳｎＯ_２から成るＩＴＯ膜（インジウム・テイン・オキサイド膜）を組み合わせた熱線反射フィルタが知られている（例えば、特許文献３及び特許文献４参照）。この熱線反射フィルタは、光学多層薄膜で７８０〜１２００ｎｍの波長の熱線をカットし、ＩＴＯ膜で１２００ｎｍ以上の波長の熱線をカットする。しかしながら、この熱線反射フィルタは熱の影響を受けやすい性質を有しており、その性質が顕著に表れる耐熱試験結果を図７に示す。耐熱試験は、熱線反射フィルタのサンプルを３００℃で３５日間加熱して行われた。耐熱試験後の熱線反射フィルタは、耐熱試験前のものに比べて、ＩＴＯ膜が有する１２００ｎｍ以上の波長の熱線をカットする効果が大きく低下している。
特開２０００−３１４８０８号公報特開２００３−２７９７２６号公報特開平８−３２９７１９号公報特開平８−２４９９１４号公報 Therefore, a heat ray reflective filter is known in which an optical multilayer thin film having 10 or more layers laminated on a transparent glass substrate is combined with an ITO film (indium thein oxide film) made of In ₂ O ₃ and SnO ₂ ( For example, see Patent Literature 3 and Patent Literature 4). This heat ray reflective filter cuts heat rays with a wavelength of 780 to 1200 nm with an optical multilayer thin film, and cuts heat rays with a wavelength of 1200 nm or more with an ITO film. However, this heat ray reflective filter has a property that is easily affected by heat, and FIG. 7 shows a heat test result in which the property appears remarkably. The heat resistance test was performed by heating a sample of the heat ray reflective filter at 300 ° C. for 35 days. In the heat ray reflective filter after the heat resistance test, the effect of cutting the heat rays having a wavelength of 1200 nm or more included in the ITO film is greatly reduced as compared with that before the heat resistance test.
JP 2000-314808 A JP 2003-279726 A JP-A-8-329719 JP-A-8-249914

本発明は、上記問題を解決するためになされたものであり、４００〜８００ｎｍの可視光の透過率が向上し、８００〜２０００ｎｍの広域の熱線をカットでき、また、高温下で長時間連続使用しても熱線カット効果が低下しない高温耐久性を有する広域熱線カットフィルタを提供することを目的とする。 The present invention has been made in order to solve the above-mentioned problems. The visible light transmittance of 400 to 800 nm is improved, a wide range of heat rays of 800 to 2000 nm can be cut, and continuous use at a high temperature for a long time. It aims at providing the wide area | region heat ray cut filter which has high temperature durability in which a heat ray cut effect does not fall even if it is.

上記目的を達成するために請求項１の発明は、透明基板と、前記透明基板の片面又は両面に光学多層膜とを備える広域熱線カットフィルタにおいて、前記光学多層膜は、前記透明基板上に高屈折率材料層と低屈折率材料層とが交互に積層され、略１０００〜２０００ｎｍの波長の熱線を反射する第１の反射部と、前記第１の反射部上に高屈折率材料層と低屈折率材料層とが交互に積層され、略８００〜１３００ｎｍの波長の熱線を反射する第２の反射部とを有し、前記第１の反射部は、設計波長をλとするとき、前記高屈折率材料層であって光学膜厚がλ／４より薄い層、前記低屈折率材料層であって光学膜厚がλ／４より薄い層、前記高屈折率材料層であって光学膜厚がλ／４以上の厚い層が順に積層されている第１の構造と、前記低屈折率材料層であって光学膜厚がλ／４より薄い層、前記高屈折率材料層であって光学膜厚がλ／４より薄い層、前記低屈折率材料層であって光学膜厚がλ／４以上の厚い層が順に積層されている第２の構造とを有し、前記第１の構造と前記第２の構造は、交互に重ねられ、前記第１の構造と前記第２の構造との間の少なくとも一部に、光学膜厚がλ／４以上の厚い層が複数挟まれたものである。
In order to achieve the above object, the invention according to claim 1 is a wide-area heat ray cut filter comprising a transparent substrate and an optical multilayer film on one or both sides of the transparent substrate, wherein the optical multilayer film is high on the transparent substrate. A refractive index material layer and a low refractive index material layer are alternately stacked, a first reflective portion that reflects heat rays having a wavelength of approximately 1000 to 2000 nm, and a high refractive index material layer and a low refractive index layer on the first reflective portion. The refractive index material layers are alternately stacked, and have a second reflecting portion that reflects heat rays having a wavelength of approximately 800 to 1300 nm. When the design wavelength is λ, the first reflecting portion A refractive index material layer having an optical film thickness smaller than λ / 4, a low refractive index material layer having an optical film thickness thinner than λ / 4, and a high refractive index material layer having an optical film thickness. A first structure in which thick layers of λ / 4 or more are sequentially laminated, and the low refractive index A material layer having an optical film thickness of less than λ / 4, the high refractive index material layer having an optical film thickness of less than λ / 4, and the low refractive index material layer having an optical film thickness of λ. / 4 or more thick layers in order, and the first structure and the second structure are alternately stacked , and the first structure and the second structure A plurality of thick layers having an optical film thickness of λ / 4 or more are sandwiched between at least a part between them.

請求項２の発明は、請求項１に記載の広域熱線カットフィルタにおいて、前記高屈折率材料層はＴａ成分から成り、かつ、前記低屈折率材料層はＳｉ成分から成るものである。 According to a second aspect of the present invention, in the wide-area heat ray cut filter according to the first aspect, the high refractive index material layer is made of a Ta component, and the low refractive index material layer is made of a Si component.

請求項３の発明は、請求項１に記載の広域熱線カットフィルタにおいて、前記高屈折率材料層はＮｂ成分から成り、かつ、前記低屈折率材料層はＳｉ成分から成るものである。 According to a third aspect of the present invention, in the wide-area heat ray cut filter according to the first aspect, the high refractive index material layer is composed of an Nb component, and the low refractive index material layer is composed of a Si component.

請求項４の発明は、請求項１乃至請求項３のいずれか一項に記載の広域熱線カットフィルタが光出射口近傍に設けられる照明器具である。 A fourth aspect of the present invention is a lighting fixture in which the wide-area heat ray cut filter according to any one of the first to third aspects is provided in the vicinity of the light exit port.

請求項１乃至請求項３の発明によれば、４００〜８００ｎｍの波長の可視光に対する透過率が８０％以上であり、８００〜２０００ｎｍの波長の熱線を５０％以上カットし、３００℃を越える高温下で長時間連続使用しても熱線カット効果が低下しない。 According to invention of Claim 1 thru | or 3, the transmittance | permeability with respect to the visible light of a wavelength of 400-800 nm is 80% or more, cuts the heat ray of a wavelength of 800-2000 nm 50% or more, and high temperature exceeding 300 degreeC. Even if it is used continuously for a long time under, the heat ray cutting effect does not decrease.

請求項４の発明によれば、熱線カット効果及び可視光の透過率が高いので、被照射物の表面温度の上昇を抑制し、かつ、効率良く可視光を照射できる。 According to the invention of claim 4, since the heat ray cutting effect and the visible light transmittance are high, an increase in the surface temperature of the irradiated object can be suppressed, and visible light can be irradiated efficiently.

本発明の一実施形態に係る広域熱線カットフィルタ（以下、カットフィルタという）について図１及び図２を参照して説明する。図１は本実施形態のカットフィルタ１を備える照明器具２の概略構成を示す。本実施形態のカットフィルタ１は、照明器具２の光出射口近傍に設けられる。照明器具２は、適宜に反射鏡４が設けられる。ハロゲンランプである光源３から出射された光５は、直接、カットフィルタ１を透過し、又は反射鏡４によって反射された後にカットフィルタ１を透過し、透過光６となって外部に出射される。照明器具２は、カットフィルタ１が熱線をカットすると共に、可視光を透過させるので、被照射物の表面温度の上昇を抑制し、かつ、効率良く可視光を照射できる。 A wide-area heat ray cut filter (hereinafter referred to as a cut filter) according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 shows a schematic configuration of a lighting fixture 2 including a cut filter 1 of the present embodiment. The cut filter 1 of the present embodiment is provided in the vicinity of the light exit of the lighting fixture 2. The lighting fixture 2 is appropriately provided with a reflecting mirror 4. The light 5 emitted from the light source 3 that is a halogen lamp is directly transmitted through the cut filter 1 or reflected by the reflecting mirror 4 and then transmitted through the cut filter 1 to be transmitted to the outside as transmitted light 6. . Since the cut filter 1 cuts the heat rays and transmits visible light, the lighting fixture 2 can suppress the increase in the surface temperature of the irradiated object and can efficiently radiate visible light.

図２は本実施形態のカットフィルタ１の概略構成を示す。カットフィルタ１は、透明基板７と、透明基板７の片面に光学多層膜８とを備える。光学多層膜８は、透明基板７上に高屈折率材料層９と低屈折率材料層１０とが交互に積層され、略１０００〜２０００ｎｍの波長の熱線を反射する第１の反射部１１を有する。また、光学多層膜８は、第１の反射部１１上に高屈折率材料層９と低屈折率材料層１０とが交互に積層され、略８００〜１３００ｎｍの波長の熱線を反射する第２の反射部１２とを有する。具体的には、光学多層膜８は、例えば、高屈折率材料層９と低屈折率材料層１０とが交互に１層〜３７層まで積層される第１の反射部１１と、高屈折率材料層９と低屈折率材料層１０とが交互に３８層〜４６層まで積層される第２の反射部１２とを有する。カットフィルタ１は、光学多層膜８が設けられている側から入射した光５に含まれる可視光を透過させると共に、光５に含まれる熱線をカットする。 FIG. 2 shows a schematic configuration of the cut filter 1 of the present embodiment. The cut filter 1 includes a transparent substrate 7 and an optical multilayer film 8 on one surface of the transparent substrate 7. The optical multilayer film 8 includes a first reflecting portion 11 in which a high refractive index material layer 9 and a low refractive index material layer 10 are alternately stacked on a transparent substrate 7 and reflects heat rays having a wavelength of about 1000 to 2000 nm. . The optical multilayer film 8 is a second layer in which high refractive index material layers 9 and low refractive index material layers 10 are alternately stacked on the first reflecting portion 11 to reflect heat rays having a wavelength of approximately 800 to 1300 nm. And a reflecting portion 12. Specifically, the optical multilayer film 8 includes, for example, a first reflecting portion 11 in which a high refractive index material layer 9 and a low refractive index material layer 10 are alternately stacked from 1 to 37 layers, and a high refractive index. The material layer 9 and the low-refractive-index material layer 10 have the 2nd reflection part 12 on which 38 to 46 layers are laminated | stacked alternately. The cut filter 1 transmits visible light included in the light 5 incident from the side where the optical multilayer film 8 is provided, and cuts heat rays included in the light 5.

透明基板７の材質は、耐熱性を高めるために風冷強化された石英ガラス、硼珪酸ガラス（硬質ガラス）、ソーダライムガラス等が挙げられるが、特に限定されるものではない。また、透明基板７の形状は、カットフィルタ１を適用する照明器具２の形状に応じて適宜に形成される。 Examples of the material of the transparent substrate 7 include quartz glass, borosilicate glass (hard glass), soda lime glass, and the like that are air-cooled and tempered to enhance heat resistance, but are not particularly limited. Moreover, the shape of the transparent substrate 7 is appropriately formed according to the shape of the lighting fixture 2 to which the cut filter 1 is applied.

高屈折率材料層９の材質は、高温耐久性及び可視光線透過性能の点からＴａ_２Ｏ_５、Ｎｂ_２Ｏ_５等が望ましい。なお、ＴｉＯ_２も高屈折率を有するが、可視光の波長を吸収して可視光線透過性能が悪いので、目標の可視光線透過率が得られないため、高屈折率材料層９の材質として望ましくない。低屈折率材料層１０の材質は、ＭｇＦ_２、ＳｉＯ_２等が挙げられるが、高温耐久性の点からＳｉＯ_２が望ましい。高屈折率材料層９及び低屈折率材料層１０は、Ｉｎ成分、及びＳｎ成分を含有していないので、３００℃を越える高温下で長時間連続使用しても熱線カット効果が低下せず、また、高温下で変色するＡｇ成分を含有していないので、高温下で長時間連続使用しても可視光の照射を阻害しない。 The material of the high refractive index material layer 9 is preferably Ta ₂ O ₅ , Nb ₂ O ₅ or the like from the viewpoint of high temperature durability and visible light transmission performance. Although TiO ₂ also has a high refractive index, the visible light transmittance is poor because it absorbs the wavelength of visible light, so that the target visible light transmittance cannot be obtained, so that it is desirable as the material of the high refractive index material layer 9. Absent. Examples of the material of the low refractive index material layer 10 include MgF ₂ and SiO ₂ , and SiO ₂ is preferable from the viewpoint of high temperature durability. Since the high refractive index material layer 9 and the low refractive index material layer 10 do not contain the In component and the Sn component, the heat ray cutting effect does not deteriorate even when continuously used at a high temperature exceeding 300 ° C. for a long time, Further, since it does not contain an Ag component that changes color at high temperatures, it does not inhibit visible light irradiation even when used continuously for a long time at high temperatures.

第１の反射部１１は、設計波長をλとするとき、高屈折率材料層９であって光学膜厚がλ／４より薄い層（以下、薄い層という）、低屈折率材料層１０であって薄い層、高屈折率材料層９であって光学膜厚がλ／４以上の厚い層（以下、厚い層という）が順に積層されている第１の構造１３を有する。また、第１の反射部１１は、低屈折率材料層１０であって薄い層、高屈折率材料層９であって薄い層、低屈折率材料層１０であって厚い層が順に積層されている第２の構造１４と有する。そして、第１の構造１３と第２の構造１４は交互に重ねられている。すなわち、第１の反射部１１は、高屈折率材料層９と低屈折率材料層１０とが交互に積層され、かつ、厚い層と厚い層との間に薄い層が２層が挟まれている構造を複数有する。 The first reflecting portion 11 is a high refractive index material layer 9 having an optical film thickness thinner than λ / 4 (hereinafter referred to as a thin layer) and a low refractive index material layer 10 when the design wavelength is λ. The first structure 13 has a thin layer and a high refractive index material layer 9 and a thick layer (hereinafter referred to as a thick layer) having an optical film thickness of λ / 4 or more. The first reflecting portion 11 includes a low refractive index material layer 10 that is a thin layer, a high refractive index material layer 9 that is a thin layer, and a low refractive index material layer 10 that is a thick layer that are stacked in order. And has a second structure 14. The first structures 13 and the second structures 14 are alternately stacked. That is, the first reflecting portion 11 includes the high refractive index material layer 9 and the low refractive index material layer 10 alternately stacked, and two thin layers are sandwiched between the thick layer and the thick layer. Have multiple structures.

また、第１の反射部１１は、例えば、第２の構造１４、高屈折率材料層９の厚い層、低屈折率材料層１０の厚い層、第１の構造１３が順に積層されている構造のような、第１の構造１３と第２の構造１４の間に複数の厚い層が挟まれる構造を有していてもよい。第１の反射部１１の最上部における構造は、例えば、第１の構造１３、低屈折率材料層１０の薄い層、高屈折率材料層９の薄い層が順に積層されている構造のような、第１の構造１３又は第２の構造１４の上に複数の薄い層が積層される構造を有していてもよい。 Moreover, the 1st reflection part 11 is the structure where the 2nd structure 14, the thick layer of the high refractive index material layer 9, the thick layer of the low refractive index material layer 10, and the 1st structure 13 are laminated | stacked in order, for example. As described above, a plurality of thick layers may be sandwiched between the first structure 13 and the second structure 14. The structure at the top of the first reflecting portion 11 is, for example, a structure in which the first structure 13, the thin layer of the low refractive index material layer 10, and the thin layer of the high refractive index material layer 9 are sequentially laminated. A plurality of thin layers may be stacked on the first structure 13 or the second structure 14.

カットフィルタ１は、第１の反射部１１が上記のように設計されることにより、略４００〜８００ｎｍの波長の可視光の透過率が８０％以上となり、略８００〜２０００ｎｍの波長の熱線を５０％以上カットできる。また、カットフィルタ１は、可視光領域の透過スペクトルにディンプルが発生することを抑えるので、透過光６に色むらが発生しない。 In the cut filter 1, the first reflecting portion 11 is designed as described above, whereby the transmittance of visible light having a wavelength of approximately 400 to 800 nm is 80% or more, and heat rays having a wavelength of approximately 800 to 2000 nm are reduced to 50%. % Or more can be cut. Further, the cut filter 1 suppresses the occurrence of dimples in the transmission spectrum in the visible light region, so that no color unevenness occurs in the transmitted light 6.

第２の反射部１２は、高屈折率材料層９の厚い層と低屈折率材料層１０の厚い層とが交互に積層される構造を有する。また、第２の反射部１２の最上部は、高屈折率材料層９の厚い層上に低屈折率材料層１０の薄い層、又は低屈折率材料層１０の厚い層上に高屈折率材料層９の薄い層が積層されていてもよい。 The second reflecting portion 12 has a structure in which a thick layer of the high refractive index material layer 9 and a thick layer of the low refractive index material layer 10 are alternately stacked. In addition, the uppermost part of the second reflecting portion 12 is a thin layer of the low refractive index material layer 10 on the thick layer of the high refractive index material layer 9 or a high refractive index material on the thick layer of the low refractive index material layer 10. A thin layer of the layer 9 may be laminated.

製膜方法は、高屈折率材料層９及び低屈折率材料層１０の薄い層を極薄膜に構成するために、略３０〜５０ｎｍである膜厚を精度良く製膜でき、かつ、高温度でも剥離が起きない膜密度及び圧縮応力が得られるイオンアシスト蒸着、プラズマ蒸着、反応性スパッタリング等が挙げられるが、特に限定されるものではない。 The film forming method can form a thin film of the high refractive index material layer 9 and the low refractive index material layer 10 into an ultrathin film with a film thickness of about 30 to 50 nm with high accuracy, and even at a high temperature. Examples include, but are not limited to, ion-assisted vapor deposition, plasma vapor deposition, and reactive sputtering that can provide a film density and compressive stress that do not cause peeling.

図３は、カットフィルタ１の変形例の構成を示す。カットフィルタ１５の構成は、上記実施形態と比べ、透明基板７の両面に光学多層膜８が設けられる点で異なる。カットフィルタ１５は、上記実施形態と同じ設計の光学多層膜８が透明基板７の両面に設けられ、光学多層膜８が片面にのみ設けられたカットフィルタ１よりも高い可視光の透過率及び熱線カット効果が得られる。 FIG. 3 shows a configuration of a modified example of the cut filter 1. The configuration of the cut filter 15 is different from that in the above embodiment in that the optical multilayer film 8 is provided on both surfaces of the transparent substrate 7. The cut filter 15 has higher visible light transmittance and heat rays than the cut filter 1 in which the optical multilayer film 8 having the same design as the above embodiment is provided on both surfaces of the transparent substrate 7 and the optical multilayer film 8 is provided only on one surface. A cutting effect is obtained.

次に、上述した実施形態を具現化した４つの実施例について説明する。 Next, four examples embodying the above-described embodiment will be described.

（実施例１）
厚さ１００ｍｍのガラス基板（商品名：ＴＥＭＰＡＸ、ＳＣＨＯＴＴ社製）である透明基板７を、弱アルカリ性のガラス用洗浄剤中で超音波洗浄した後に、純水で洗浄してから１３０℃で６０分間乾燥させる。次に、透明基板７の温度を２００℃にして、酸素ガスを導入させた状態で、高屈折率材料層９の材質であるＴａ_２Ｏ_５と低屈折率材料層１０の材質であるＳｉＯ_２を、イオンアシスト蒸着法によって交互に４６層積層させて、透明基板７の片面に光学多層膜８を形成させることでカットフィルタ１を得た。表１に高屈折率材料層９及び低屈折率材料層１０の各光学膜厚を示す。光学膜厚の欄に記載された値は、設計波長λを８５０ｎｍとしたときのλ／４の値を１として算出した値である。この値とλ／４との積が光学膜厚を示す。 Example 1
The transparent substrate 7 which is a glass substrate having a thickness of 100 mm (trade name: TEMPAX, manufactured by SCHOTT) was ultrasonically cleaned in a weak alkaline glass cleaner, then washed with pure water and then at 130 ° C. for 60 minutes. dry. Next, in a state where the temperature of the transparent substrate 7 is set to 200 ° C. and oxygen gas is introduced, Ta ₂ O ₅ that is the material of the high refractive index material layer 9 and SiO ₂ that is the material of the low refractive index material layer 10. 46 layers were alternately laminated by ion-assisted vapor deposition, and the optical multilayer film 8 was formed on one side of the transparent substrate 7 to obtain the cut filter 1. Table 1 shows the optical film thicknesses of the high refractive index material layer 9 and the low refractive index material layer 10. The value described in the column of the optical film thickness is a value calculated by setting the value of λ / 4 when the design wavelength λ is 850 nm as 1. The product of this value and λ / 4 indicates the optical film thickness.

次に、上記のように作製した実施例１のカットフィルタ１のサンプルを５００℃で３０日間加熱する耐熱試験を行った。 Next, the heat resistance test which heats the sample of the cut filter 1 of Example 1 produced as mentioned above at 500 degreeC for 30 days was done.

耐熱試験前と耐熱試験後のそれぞれのカットフィルタ１における分光透過特性を、株式会社日立ハイテクノロジー製、自記分光光度計Ｕ−４０００を用いて測定した。この分光透過特性の測定結果を図４に示す。図４から分かるように、耐熱試験前と耐熱試験後では、カットフィルタ１の分光透過特性に全く変化が無かった。そのため、カットフィルタ１は、高温下で長時間連続使用しても熱線カット効果が低下しない。また、可視光領域の透過スペクトルにディンプルがほとんど発生していないので、透過光６に色むらが生じない。なお、耐熱試験前及び耐熱試験後のいずれも、カットフィルタ１の可視光平均透過率が９０％、８００〜２０００ｎｍの波長の熱線カット率は７６％であった。 Spectral transmission characteristics of each cut filter 1 before and after the heat test were measured using a self-recording spectrophotometer U-4000 manufactured by Hitachi High-Technology Corporation. The measurement result of this spectral transmission characteristic is shown in FIG. As can be seen from FIG. 4, there was no change in the spectral transmission characteristics of the cut filter 1 before and after the heat test. Therefore, even if the cut filter 1 is continuously used at a high temperature for a long time, the heat ray cutting effect does not deteriorate. Further, since almost no dimples are generated in the transmission spectrum in the visible light region, the transmitted light 6 does not have color unevenness. In addition, both before the heat test and after the heat test, the visible light average transmittance of the cut filter 1 was 90%, and the heat ray cut rate at a wavelength of 800 to 2000 nm was 76%.

（実施例２）
表１に示される４６層の光学多層膜８を、透明基板７の両面にそれぞれ形成した以外は、実施例１と同様にしてカットフィルタ１５を得た。次に、実施例１と同様の耐熱試験を行った。耐熱試験前と耐熱試験後のそれぞれのカットフィルタ１５における分光透過特性の測定結果を図５に示す。図５から分かるように、耐熱試験前と耐熱試験後では、カットフィルタ１５の分光透過特性に全く変化が無かった。そのため、カットフィルタ１５は、高温下で長時間連続使用しても熱線カット効果が低下しない。また、可視光領域の透過スペクトルにディンプルがほとんど発生していないので、透過光６に色むらが生じない。なお、耐熱試験前及び耐熱試験後のいずれも、カットフィルタ１５の可視光平均透過率が９１．５％、８００〜２０００ｎｍの波長の熱線カット率が８３％であった。また、カットフィルタ１５は、耐熱試験前と耐熱試験後のいずれの場合も、可視光平均透過率及び熱線カット率が実施例１のカットフィルタ１より優れていた。 (Example 2)
A cut filter 15 was obtained in the same manner as in Example 1 except that the 46-layer optical multilayer film 8 shown in Table 1 was formed on both surfaces of the transparent substrate 7 respectively. Next, the heat resistance test similar to Example 1 was done. FIG. 5 shows the measurement results of the spectral transmission characteristics in the respective cut filters 15 before and after the heat test. As can be seen from FIG. 5, there was no change in the spectral transmission characteristics of the cut filter 15 before and after the heat test. Therefore, even if the cut filter 15 is continuously used at a high temperature for a long time, the heat ray cutting effect does not deteriorate. Further, since almost no dimples are generated in the transmission spectrum in the visible light region, the transmitted light 6 does not have color unevenness. In addition, both before the heat test and after the heat test, the visible light average transmittance of the cut filter 15 was 91.5%, and the heat ray cut rate at a wavelength of 800 to 2000 nm was 83%. The cut filter 15 was superior to the cut filter 1 of Example 1 in the visible light average transmittance and the heat ray cut rate in both cases before and after the heat test.

（実施例３）
高屈折率材料層９の材質をＮｂ_２Ｏ_５にした以外は、実施例１と同様にしてカットフィルタ１を得た。次に、実施例１と同様の耐熱試験を行った。耐熱試験前と耐熱試験後のそれぞれのカットフィルタ１の分光透過特性を測定した。耐熱試験前と耐熱試験後では、広域熱線カットフィルタの分光透過特性に全く変化が無かった。そのため、カットフィルタ１は、高温下で長時間連続使用しても熱線カット効果が低下しない。また、カットフィルタ１は、耐熱試験前及び耐熱試験後のいずれの場合も、可視光平均透過率が９０．５％、８００〜２０００ｎｍの波長の熱線カット率が７０％であった。 (Example 3)
A cut filter 1 was obtained in the same manner as in Example 1 except that the material of the high refractive index material layer 9 was changed to Nb ₂ O ₅ . Next, the heat resistance test similar to Example 1 was done. The spectral transmission characteristics of each cut filter 1 before and after the heat test were measured. Before and after the heat test, there was no change in the spectral transmission characteristics of the wide-area heat ray cut filter. Therefore, even if the cut filter 1 is continuously used at a high temperature for a long time, the heat ray cutting effect does not deteriorate. The cut filter 1 had a visible light average transmittance of 90.5% and a heat ray cut rate of a wavelength of 800 to 2000 nm of 70% before and after the heat test.

（実施例４）
実施例２で得られたカットフィルタ１５を、光源３として１０００Ｗのハロゲンランプを用いた舞台用スポットライト照明器具である照明器具２の光出射口近傍に設置した。照明器具２を点灯させ、４ｍ離れた被照射物の表面温度の測定を行った。被照射物の表面温度は、カットフィルタ１５を設置せずに光源３から光を照射させたときと比較すると８．５℃低くなった。カットフィルタ１５が設置された照明器具２の中心照度は、ＩＴＯ膜を用いた現行品の照明器具と比較して２４％向上した。また、ＩＴＯ膜を用いた現行品の照明器具の熱線カット効果は、２００〜３００時間の連続使用後に効果が半減したのに対して、カットフィルタ１５の照明器具２の熱線カット効果は、５０００時間の連続使用後も全く低下が認められなかった。 Example 4
The cut filter 15 obtained in Example 2 was installed in the vicinity of the light outlet of the luminaire 2 which is a stage spotlight luminaire using a 1000 W halogen lamp as the light source 3. The lighting fixture 2 was turned on and the surface temperature of the irradiated object 4 m away was measured. The surface temperature of the irradiated object was 8.5 ° C. lower than when the light was irradiated from the light source 3 without installing the cut filter 15. The central illuminance of the lighting fixture 2 provided with the cut filter 15 was improved by 24% compared to the current lighting fixture using an ITO film. In addition, the heat ray cutting effect of the current lighting fixture using the ITO film is halved after 200 to 300 hours of continuous use, whereas the heat ray cutting effect of the lighting fixture 2 of the cut filter 15 is 5000 hours. No decrease was observed after continuous use.

なお、本発明は、上記の実施形態の構成に限られず、発明の要旨を変更しない範囲で種々の変形が可能である。例えば、透明基板の両面に光学多層膜を設ける場合、光学多層膜を構成する高屈折率材料層及び低屈折率材料層の膜厚の設計が一方の面と他方の面で異なっていても構わない。 In addition, this invention is not restricted to the structure of said embodiment, A various deformation | transformation is possible in the range which does not change the summary of invention. For example, when providing an optical multilayer film on both surfaces of a transparent substrate, the design of the film thickness of the high refractive index material layer and the low refractive index material layer constituting the optical multilayer film may be different on one surface and the other surface. Absent.

本発明の一実施形態に係る広域熱線カットフィルタを用いた照明器具の断面図。Sectional drawing of the lighting fixture using the wide-area heat ray cut filter which concerns on one Embodiment of this invention. 同カットフィルタを示す側面図。The side view which shows the cut filter. 同カットフィルタの変形例を示す側面図。The side view which shows the modification of the cut filter. 耐熱試験前及び耐熱試験後の同カットフィルタの実施例における分光透過特性を示す図。The figure which shows the spectral transmission characteristic in the Example of the same cut filter before a heat test and after a heat test. 耐熱試験前及び耐熱試験後の同カットフィルタの他の実施例における分光透過特性を示す図。The figure which shows the spectral transmission characteristic in the other Example of the same cut filter before a heat test and after a heat test. ハロゲンランプの放射特性を示す図。The figure which shows the radiation characteristic of a halogen lamp. 耐熱試験前及び耐熱試験後の従来の熱線反射フィルタの分光透過特性を示す図。The figure which shows the spectral transmission characteristic of the conventional heat ray reflective filter before a heat test and after a heat test.

Explanation of symbols

１広域熱線カットフィルタ（カットフィルタ）
２照明器具
７透明基板
８光学多層膜
９高屈折率材料層
１０低屈折率材料層
１１第１の反射部
１２第２の反射部
１３第１の構造
１４第２の構造 1 Wide-area heat ray cut filter (cut filter)
DESCRIPTION OF SYMBOLS 2 Lighting fixture 7 Transparent substrate 8 Optical multilayer film 9 High refractive index material layer 10 Low refractive index material layer 11 1st reflection part 12 2nd reflection part 13 1st structure 14 2nd structure

Claims

In a wide area heat ray cut filter comprising a transparent substrate and an optical multilayer film on one or both sides of the transparent substrate,
The optical multilayer film includes a first reflecting portion in which a high refractive index material layer and a low refractive index material layer are alternately stacked on the transparent substrate, and reflects a heat ray having a wavelength of about 1000 to 2000 nm;
A high-refractive index material layer and a low-refractive index material layer are alternately stacked on the first reflective part, and has a second reflective part that reflects heat rays having a wavelength of approximately 800 to 1300 nm,
The first reflecting portion is
When the design wavelength is λ, the high refractive index material layer having an optical film thickness thinner than λ / 4, the low refractive index material layer having an optical film thickness thinner than λ / 4, A first structure in which a thick layer having a refractive index material layer and an optical film thickness of λ / 4 or more is sequentially laminated;
The low refractive index material layer having an optical thickness less than λ / 4, the high refractive index material layer having an optical thickness less than λ / 4, and the low refractive index material layer having an optical thickness. A second structure in which thick layers having a thickness of λ / 4 or more are sequentially stacked;
The first structure and the second structure are alternately stacked ;
A wide-area heat ray cut filter, wherein a plurality of thick layers having an optical film thickness of λ / 4 or more are sandwiched between at least a part between the first structure and the second structure .

2. The wide-area heat ray cut filter according to claim 1, wherein the high refractive index material layer is made of a Ta (tantalum) component, and the low refractive index material layer is made of a Si component.

2. The wide-area heat ray cut filter according to claim 1, wherein the high refractive index material layer is made of an Nb (niobium) component, and the low refractive index material layer is made of a Si component.

The lighting fixture in which the wide area heat ray cut filter as described in any one of Claims 1 thru | or 3 is provided in the light emission opening vicinity.