JP2005055685A - Light control member, manufacture of light control member, light controller and photographing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light control member which is actuated with a very easy operation, which has a good yield, which is inexpensive, excellent in flatness and reliability over a long period, especially, excellent in humidity-resistance, to provide a manufacturing method of the light control member, to provide a light controller and a photographing device. <P>SOLUTION: The light control member is constituted of a pair of transparent base materials and a colored layer held by the pair of transparent base materials. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light amount adjusting member used in an optical apparatus such as a digital camera or a video camera, an electrophotographic recording apparatus, or the like, a method for manufacturing the light amount adjusting member, a light amount adjusting device, and a photographing device.

  An imaging (photographing) optical system used for an optical device such as a camera generally includes a so-called diaphragm device that adjusts the amount of incident light. In such a diaphragm device, a plurality of diaphragm blades form an opening of a predetermined area, and the amount of the light beam passing through the opening is adjusted by adjusting the opening diameter of the opening with an actuator. However, as the aperture diameter of the aperture is reduced, the influence of diffraction generated at the end of the aperture blade increases, and the imaging performance of the imaging optical system decreases. On the other hand, in order to avoid this drawback, a filter as a light amount adjusting member is provided on a part of the diaphragm blade, and instead of reducing the aperture diameter, the amount of the light beam (light amount) passing through the opening with an optical filter is reduced. ) Is known. An optical filter used for such a purpose is required to have few optical defects such as light scattering, refractive error, and spectral transmittance deviation.

  Conventionally, as this light amount adjusting member, a type of colored film is generally used by mixing a light-transmitting film forming material with a coloring material such as a pigment or dye that absorbs light and kneading. ing. However, the light amount adjusting member manufactured by this method is very expensive, and cannot sufficiently meet the cost reduction required for the expanding demand. In addition, a method of kneading a color material into a light-transmitting film material to form a colored film produces a light amount adjusting member having a density distribution continuously or stepwise (hereinafter referred to as “multi-density”). It is extremely difficult to do.

  As another manufacturing method, for example, Patent Document 1 discloses a method of manufacturing a multi-concentration light amount adjusting member using a silver salt film. In this case, however, silver contained in the filter is disclosed. Use a silver salt film in which the linearity of the light beam that has passed through the filter is impaired due to the reflection of the light beam at the particle surface or the diffraction of the light beam that passes through the edge of the silver particle, thereby reducing the imaging performance of the optical system. This creates a unique problem.

  Patent Document 2 discloses a method of manufacturing a multi-concentration light amount adjusting member by vapor deposition, but this method is expensive and expensive to manufacture, and in addition, the light amount adjusting member of the light amount adjusting member depends on the concentration. Since the film thickness changes, a difference in film thickness occurs between a high density and a low density, resulting in a problem that an optical path difference occurs and the resolving power decreases. In this method, it is difficult to manufacture a product having a continuous concentration distribution, and even if manufactured, the concentration distribution changes stepwise.

  In Patent Document 3, an organic dye that fades with light is first kneaded into a film material, and the resulting film is partially irradiated with high-energy light to decompose the organic dye in the irradiated portion, thereby reducing the concentration. A method of manufacturing a light amount adjusting member having a distribution is disclosed. However, in this method, usable color materials are limited to those that fade with light, so it is very difficult to obtain a product having sufficient optical characteristics. Furthermore, it can be easily estimated from the complicated manufacturing method that the product obtained will be very expensive.

  Further, in Patent Document 4, a light intensity adjusting member that changes the transmittance steplessly by forming a single-concentration film in a halftone dot pattern by a printing process such as vapor deposition or photoengraving, and changing the halftone dot pattern depending on the location. A filter manufacturing method is disclosed. However, this method forms a film having a predetermined concentration by photoengraving or vapor deposition. Regardless of which step is employed, the apparatus becomes large and expensive, and the manufacturing cost of the filter increases. There are challenges.

  In order to solve the above problems, a filter manufacturing method as a light amount adjusting member by a liquid jet recording method has recently attracted attention. In this method, a layer made of a material capable of absorbing a colored liquid (hereinafter referred to as “colored ink” throughout the present specification) (hereinafter referred to as “ink receiving layer” throughout the present specification) is provided on the transparent substrate, A colored ink is applied to the layer by a liquid jet recording method to form a colored layer, and a planarizing layer is provided on the colored layer.

  According to the above method, it is possible to easily produce a light amount adjusting member having excellent performance, but when the ink receiving layer is formed by coating on a transparent substrate, the flatness of the coating film is realized. If it is difficult and the surface is not flat, a difference in optical path length due to a difference in film thickness in the coating film may impair optical characteristics. Further, since the ink receiving layer is directly exposed to the outside air, the ink receiving layer swells due to absorption of moisture in the air under long-term storage or high humidity conditions. As a result, the light amount adjusting member As a result, the film thickness at the peripheral portion increases, and a problem arises in that the optical path difference occurs and the resolving power decreases.

JP-A-5-173004 JP-A-10-133254 Japanese Patent Laid-Open No. 10-96971 JP 2000-352736 A

Therefore, the object of the present invention is to solve the above-mentioned problems of the prior art, to manufacture the light amount adjusting member economically by a simple operation with low manufacturing cost, high yield, and further reliability, In particular, an object of the present invention is to provide a light amount adjusting member having excellent moisture resistance and a manufacturing method thereof.
In addition to the above, an object of the present invention is to provide a method of manufacturing a light amount adjusting member that can easily obtain a light amount adjusting member having a concentration distribution continuously or stepwise.
Furthermore, an object of the present invention is to provide a light amount adjusting member which is manufactured by the above-described simple manufacturing method and has an inexpensive and excellent characteristic and has high reliability, and a light amount adjusting device and a photographing device including the light amount adjusting member. Is to provide.

  The above object is achieved by the present invention described below. That is, the present invention provides a light amount adjusting member comprising a pair of transparent base materials and a colored layer sandwiched between the pair of transparent base materials.

  In the present invention, a transparent adhesive layer is formed between the pair of transparent substrates and the colored layer; an end surface of the colored layer is sealed with the adhesive layer; and The colored layer preferably has a concentration distribution continuously or stepwise.

  The present invention also includes a step of providing an ink receiving layer on a transfer substrate, a step of forming a colored layer by applying a colored ink to the layer by a liquid jet recording method, There is provided a method for producing a light amount adjusting member, comprising a step of transferring onto a transparent substrate and a step of laminating a second transparent substrate on the release surface of the transferred colored layer.

  In the method of the present invention, the transfer substrate has a release layer; the colored layer is transferred onto the first transparent substrate through a transparent adhesive layer provided on the colored layer. Applying the colored ink so that the colored layer has a concentration distribution continuously or stepwise; and the adhesive layer is formed so as to seal an end face of the colored layer, It is preferable that a partial change in the optical path length caused by moisture absorption of the layer is prevented: and a part of the colored layer is removed and the end face of the colored layer is sealed with the adhesive layer.

  Further, the present invention provides a light amount adjusting member manufactured by the above manufacturing method; a light amount adjusting device including the light amount adjusting member; and the light amount adjusting device and a subject image. A photographing optical system for forming the image, an imaging means for photoelectrically converting the formed subject image, and a recording means for recording the photoelectrically converted signal, and the light amount adjusting device is disposed in the photographing optical system. An imaging apparatus is provided.

  According to the present invention, there are provided a light amount adjusting member, a manufacturing method thereof, a light amount adjusting device, and a photographing device that are very simple operation, low in yield, excellent in flatness, long-term reliability, and particularly excellent in moisture resistance. Is done. Further, according to the present invention, it is possible to simply provide a light amount adjusting member having a density distribution in a continuous or stepwise manner, which is extremely difficult in other manufacturing methods.

Next, the present invention will be described in more detail with reference to the best mode for carrying out the invention. First, the light amount adjusting member of the present invention will be described together with the method for manufacturing the light amount adjusting member of the present invention.
An outline of a method for manufacturing a light amount adjusting member according to the present invention will be described with reference to FIG. First, a release layer is provided on the transfer substrate as required (a). When the transfer substrate has sufficient release properties, the formation of the release layer can be omitted. Next, an ink receiving layer is provided on the surface of the release layer (b), and colored ink is applied to the ink receiving layer from the ink jet head of the liquid jet recording apparatus to form a colored layer (c). If necessary, a first adhesive layer is formed on the release surface of the colored layer (d). Next, the adhesive layer is laminated to face the first transparent substrate (e), and the transfer substrate is peeled off (f). On the other hand, if necessary, a second adhesive layer is formed on the second transparent substrate (g), and the release surface of the ink receiving layer from which the transfer substrate has been peeled is opposed to the second adhesive layer. To obtain a light amount adjusting member of the present invention. An antireflection film can be formed on the release surfaces of the first and second transparent substrates (h). In the above process, when the ink receiving layer or the colored layer has sufficient adhesion to the first and second transparent substrates, the formation of the first and second adhesive layers is not essential.

  Next, another embodiment of the manufacturing method of the present invention will be described with reference to FIG. The process up to the formation of the colored layer is the same as the manufacturing method shown in FIG. 1 (a). A part of the formed colored layer is removed (b). Examples of the method for removing the colored layer include a method of removing a part of the colored layer by irradiating a laser beam, a method of removing a part of the colored layer using a photolithography method, a tool such as a cutter knife, and the like. There is no particular limitation as long as the function as the adjusting member is not damaged. The laser beam used at that time is not particularly limited as long as a part of the colored layer can be removed, and examples thereof include a YAG laser, an excimer laser, and a carbon dioxide gas laser.

  Next, a first adhesive layer is formed on the entire surface including the colored layer (c), and the steps (d) to (f) are performed in the same manner as shown in FIG. 1 to obtain the light quantity adjusting member of the present invention. It is done. By cutting the light amount adjusting member at a place where the colored layer does not exist (g), the end face of the colored layer is sealed by the adhesive layer, and a partial change in the optical path length caused by moisture absorption of the colored layer is prevented. The light quantity adjusting member (h) of the present invention is obtained. Therefore, the adhesive layer also functions as a moisture-proof layer.

  The thickness of each member used in the present invention varies depending on the performance required for the light amount adjusting member, but the thickness of the release layer is generally 0.1 to 10 μm, and the thickness of the ink receiving layer is It is generally 1 to 15 μm, the thickness of the first and second adhesive layers is generally 0.1 to 10 μm, and the thickness of the first and second transparent substrates is generally 50 to 2, The thickness of the antireflection film is generally 0.1 to 10 μm.

  The transfer substrate used in the present invention is not particularly limited as long as it has flatness that realizes surface flatness of the light amount adjusting member. For example, a metal plate, polished glass, a silicon substrate, etc. can be mentioned. However, it is preferable that the material is stable against high-temperature heating.

  Specific materials for the release agent used to form a release layer on the transfer substrate include waxes such as carnauba wax, paraffin wax, microcrystalline wax, and castor wax, stearic acid, and palmitic acid. Higher fatty acids such as acid, lauric acid, aluminum stearate, lead stearate, barium stearate, zinc stearate, zinc palmitate, methylhydroxystearate, glycerin monohydroxystearate, or metal salts, derivatives such as esters, Polyamide resins, petroleum resins, rosin derivatives, chroman-indene resins, terpene resins, novolac resins, styrene resins, polyethylene, polypropylene, polybutene, olefin resins such as polyolefin oxide, vinyl ether resins, etc. It is below. In addition, silicone resins, fluorosilicone resins, fluoroolefin vinyl ether terpolymers, perfluoroepoxy resins, thermosetting acrylic resins having a perfluoroalkyl group in the side chain, fluororesins, vinylidene fluoride curable resins, etc. These can be used singly or in combination, but of course the present invention is not limited to these.

  In the present invention, as the coating liquid material in the case of forming the ink receiving layer on the transfer substrate (or release layer), the colored ink is absorbed in the ink receiving layer formed by the material, and the colored ink The water-soluble resin and water-dispersible resin listed below are preferably used as long as they can receive and fix the color material therein.

  Examples of the water-soluble resin include polyvinyl alcohol and modified products of polyvinyl alcohol such as anion-modified polyvinyl alcohol, cation-modified polyvinyl alcohol, and acetal-modified polyvinyl alcohol; water-based polyurethane; polyvinyl pyrrolidone, and a copolymer of vinyl pyrrolidone and vinyl acetate. , Vinylpyrrolidone and dimethylaminoethyl / methacrylic acid copolymer, quaternized vinylpyrrolidone and dimethylaminoethyl / methacrylic acid copolymer, vinylpyrrolidone and methacrylamidopropyl trimethylammonium chloride copolymer, etc. Modified products of: cellulose-based water-soluble resins such as carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, and cationized hydroxyethyl Modified cellulose, such as roulose; polyester, polyacrylic acid (ester), melamine resin, or modified products thereof, synthetic resin such as graft copolymer containing at least polyester and polyurethane, albumin, gelatin, casein, Listed are natural resins such as starch, cationized starch, gum arabic, and sodium alginate.

  Examples of the water dispersible resin include polyvinyl acetate, ethylene-vinyl acetate copolymer, polystyrene, styrene- (meth) acrylate copolymer, (meth) acrylate polymer, vinyl acetate- (Meth) acrylic acid (ester) copolymer, poly (meth) acrylamide, (meth) acrylamide copolymer, styrene-isoprene copolymer, styrene-butadiene copolymer, styrene-propylene copolymer, polyvinyl ether , Silicone-acrylic copolymers and the like can be listed, but of course the present invention is not limited to these. Among these, resins having excellent heat resistance such as acetal-modified polyvinyl alcohol, water-based polyurethane, hydroxypropyl cellulose, polyester, polyacrylic acid, and melamine resin are particularly preferably used.

  In addition, a gap absorption type in which the above water-soluble resin or water-dispersible resin is used as a binder and pigments such as alumina hydrate, silica, calcium carbonate, etc. are mixed with these materials has optical characteristics. It can be used within the range to satisfy.

  Furthermore, in addition to the above materials, the coating liquid may contain various surfactants, cross-linking agents, and dyes as necessary for controlling coating properties, absorbing performance of colored inks, improving mechanical properties, and the like. A fixing agent (waterproofing agent), an antifoaming agent, an antioxidant, a viscosity adjusting agent, a pH adjusting agent, an antifungal agent, a plasticizer, and the like may be contained.

  In the present invention, a coating liquid containing the above materials is applied onto a transfer substrate to form an ink receiving layer, and a colored ink is applied to the layer by a liquid jet recording method. A colored layer is formed by absorbing and receiving the ink in the ink receiving layer, and the light amount adjusting member is formed by the method shown in FIGS. 1 and 2, and the colored ink used in this case is a micro droplet discharge device. There is no particular limitation as long as it can be discharged.

  In the present invention, both a water-based ink and an oil-based ink can be used as the colored ink, but it is preferable to use a water-based colored ink from the viewpoint of ejection reliability. As the coloring material in the colored ink, various dyes and pigments can be used, but various metals, inorganic fine particles, organic fine particles, and the like can also be used. In the present invention, the color material constituting the colored ink refers to a material that controls the transmittance of light in a predetermined wavelength band including visible light, ultraviolet light, and infrared light. That is, in the manufacture of the light amount adjusting member exemplified in the present specification, a colorant that gives uniform transmission characteristics over the entire visible light band is used, but the present invention is not limited to this. Absent. For example, when forming a light amount adjusting member used in a light amount adjusting device for an infrared camera, it is necessary to use a material that transmits only a specific wavelength in the infrared region, and this is also included in the color material. Furthermore, light absorption when controlling the amount of transmitted light is included in the color material used in the present invention, such as light generated inside the material or generated on the surface of the material.

  As the solvent that is a material for forming the colored ink used in the present invention, an aqueous medium is preferably used. As the aqueous medium, various water-soluble organic solvents listed below can be used. Specifically, for example, C 1-5 such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-pentanol and the like. Alkyl alcohols; amides such as dimethylformamide and dimethylacetamide; ketones or ketoalcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, Oxyethylene or oxypropylene copolymers such as tripropylene glycol, polyethylene glycol, polypropylene glycol; ethylene glycol, propylene Alkylene glycols containing 2 to 6 carbon atoms such as ethylene glycol, trimethylene glycol, 1,2,6-hexanetriol; glycerin; ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) Lower alkyl ethers such as ether and triethylene glycol monomethyl (or ethyl) ether; lower dialkyl ethers of polyhydric alcohols such as triethylene glycol dimethyl (or ethyl) ether and tetraethylene glycol dimethyl (or ethyl) ether; monoethanol Alkanolamines such as amine, diethanolamine, triethanolamine; sulfolane, N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazoli Non, and the like. The above water-soluble organic solvents can be used alone or as a mixture.

  In addition to the above-mentioned components, the colored ink used in the present invention further includes various surfactants, antifoaming agents, preservatives, etc., in order to obtain colored inks having desired physical properties as required. be able to.

  In the present invention, the colored layer of the light quantity adjusting member is formed by applying the colored ink made of the material as described above to the ink receiving layer described above by using the micro droplet ejection device. There are no particular restrictions on the method of applying colored ink by the microdroplet ejection device used at that time, for example, a bubble jet (registered trademark) type using an electrothermal transducer as an energy generating element, or a piezo using a piezoelectric element. A jet type or the like can be used. A commercially available general-purpose printer can be used as the micro droplet discharge device as the printing device, but the present invention is not limited to this, and a printing device specially manufactured for the present invention may be used.

  The pattern for applying the colored ink is not particularly limited, and may be applied to the entire surface with a uniform density depending on the purpose, or may be a gradation pattern with a stepwise density gradient as shown in FIG. Further, it may be a gradation pattern in which the gradation level with continuous density gradient is unclear. In particular, according to the manufacturing method of the present invention, a colored layer of a light amount adjusting member having a continuous or stepwise concentration gradient can be easily produced. Further, since the degree of freedom of the method of forming the density gradient pattern is high, there is also an advantage that the optical optimization of the light amount adjusting member is easy.

  In the method of the present invention, after applying the color ink as described above, if necessary, drying using a hot air drying furnace, a hot drum, a hot plate, or the like may be performed. In particular, a method in which a crosslinking agent is mixed in the ink receiving layer forming material, and the colored layer on the transfer substrate is cured by heating or light irradiation to impart moisture resistance to the colored layer is also effective. It is.

  The adhesive layer (moisture-proof layer) provided as necessary in the present invention has transparency, adhesion to the ink receiving layer, the first and second transparent substrates, and mechanical strength capable of protecting the colored layer. As long as the required performance such as optical characteristics is satisfied, there is no particular limitation. Specifically, for example, an acrylic or epoxy thermosetting resin or photocurable resin is used to form these adhesive layers. The coating liquid made of the material was applied onto the surface of the colored layer or the first and second transparent substrates to form a coating film, and the colored layer was adhered to the first or second transparent substrate. Thereafter, the adhesive is baked using an oven, a hot plate or the like, and the adhesive layer is cured and adhered, or the adhesive layer is cured by irradiating with an electron beam, ultraviolet light, or the like. Can be used.

  As a method used for forming the release layer, the ink receiving layer, or the adhesive layer (moisture-proof layer), the above-described materials may be combined with other additives as necessary, water or alcohol, polyhydric alcohols, or others. Or an appropriate organic solvent to prepare a coating liquid, and then the obtained coating liquid is, for example, a roll coater method, a blade coater method, an air knife coater method, a gate roll coater method, a bar coater method, Apply by size press method, spray coat method, gravure coater method, curtain coater method, spin coat method, etc., and then dry using, for example, hot air drying oven, hot drum, hot plate etc., release layer And a method of forming an ink receiving layer or an adhesive layer (moisture-proof layer).

  The first and second transparent substrates used in the present invention are not particularly limited as long as they have necessary characteristics such as mechanical strength and optical characteristics as a light amount adjusting member. For example, a transparent film substrate made of polyethylene terephthalate, cellulose diacetate, cellulose triacetate, cellophane, celluloid, polycarbonate, polyimide, polyvinyl chloride, polyvinylidene chloride, polyacrylate, polyethylene, polypropylene and the like can be mentioned. A glass substrate can also be used as long as it satisfies the above required characteristics.

  Furthermore, an antireflection film may be formed on both surfaces of the light amount adjusting member obtained as described above. This antireflection film is required to have excellent antireflection characteristics in the visible light band and excellent moisture and harmful gas blocking characteristics. In order to satisfy this requirement, it is preferable to use a vapor-deposited multilayer film of an inorganic material. For example, by using the antireflection film described in Japanese Patent Application Laid-Open No. 06-273601 by the applicant, stray light is prevented from being generated due to the surface reflection of the light amount adjusting member, and moisture and harmful gas enter the colored layer. And the deterioration of the color material in the colored layer can be prevented.

  The light amount adjusting member of the present invention is manufactured as described above. The optical characteristics of the light amount adjusting member of the present invention will be described. First, when judging the quality of the light amount adjusting member, (1) when used alone, the color material is deteriorated in optical performance caused by scattering or refracting the light beam, and (2) used in an aperture device or the like. In this case, it is necessary to evaluate the three items of the diffraction prevention effect and (3) spectral transmittance.

  Here, in (3), the characteristics of the light amount adjusting member can be freely adjusted according to the type of the color material to be used, and the measurement can be easily performed using a commercially available spectral transmittance meter. On the other hand, in the evaluation item (2) above, factors such as the shape of the aperture blade and the aperture value (F number) at the time of evaluation greatly affect the evaluation result. Not suitable. The method (1) is suitable for evaluating the optical characteristics of the light quantity adjusting member alone. Therefore, in each example described later, the measurement results of the optical characteristic evaluation method of the light quantity adjusting member alone and the uniform concentration light quantity adjusting member prepared by the manufacturing method of each example are described.

  The optical superiority when the optical density of the light amount adjusting member is changed stepwise or continuously is described, for example, in JP-A-6-95208 and JP-A-11-15042. On the other hand, according to the study by the present inventors, if a light amount adjusting member whose optical density that is simply manufactured by the method of the present invention is changed stepwise or continuously is applied to the diaphragm device, the above-described public It turned out that the same effect as a technique can be acquired.

  The light quantity adjusting device provided with the light quantity adjusting member obtained by the manufacturing method of the present invention will be described below. In addition, this invention is not limited to the structure described below. FIG. 3 shows a diaphragm blade which is an example of the light amount adjusting member of the present invention, and FIG. 4 is a diagram showing a diaphragm blade device provided with the light amount adjusting member. 3A is a plan view of the diaphragm blade, and FIG. 3B is a cross-sectional view taken along the line AA ′ in FIG. 3A (only the light amount adjusting member (0 to x1) is shown). . Here, a diaphragm device used in a video camera or the like will be described as an example of the light amount adjusting device. 101 in the figure shows the entire aperture blade, but as shown in the figure, a light amount adjusting member 101P (gradation part in FIG. 3) to which a predetermined transmittance is given and a light blocking member 101Q (gradation) that blocks light. And other parts). 3 and 4, the light blocking member 101Q is not colored to clarify the boundary with the light amount adjusting member 101P. However, since it is originally intended to block light, black or the like is used. It is formed with.

  FIG. 4 is a diagram illustrating an example of a light amount adjusting device using the diaphragm blades of FIG. In FIG. 4, reference numeral 100 denotes the entire light amount adjusting device. 101 is the first diaphragm blade shown in FIG. 3, and 102 is the second diaphragm blade. The second diaphragm blade 102 is manufactured by the same method as the first diaphragm blade, and includes a light amount adjusting member 102P and a light blocking member 102Q. Reference numeral 103 denotes a diaphragm blade drive lever that is fitted to a shaft of a motor (not shown) in a hole 103a and rotated around the hole 103a. The first diaphragm blade 101 and the second diaphragm blade 102 are engaged with the projecting pins 103b and 103c at both ends of the diaphragm blade driving lever 103 in the respective groove holes 101a and 102a. Reference numeral 105 denotes a guide pin of a ground plate (not shown) that is slidably engaged with the grooves 101b and 102b on the side edges of the first and second diaphragm blades 101 and 102, and 106 denotes a ground plate. The optical path holes 101c and 102c that are provided are the aperture opening edges of the first and second diaphragm blades 101 and 102, respectively.

  FIG. 4 shows a state when the aperture is fully open. When the diaphragm is narrowed from the fully open state, the optical path hole 106 which is the aperture of the diaphragm is shielded by the light transmitting portions 101P and 102P of the first and second diaphragm blades, and the aperture diameter becomes small. The transmittance (light quantity) of the light beam passing through the optical path hole 106 gradually decreases.

  FIG. 5 is a schematic layout diagram when the light amount adjusting device shown in FIG. 4 is arranged in an optical device. In the present embodiment, an optical apparatus will be described by taking as an example a video camera that photoelectrically converts a moving image or a still image into an electrical signal by an imaging means and records this as digital data. A photographing optical system 400 includes a plurality of lens groups, and includes a first lens group 401, a second lens group 402, a third lens group 403, and the diaphragm apparatus 100 shown in FIG. Reference numeral 401 denotes a fixed front lens group, 402 denotes a variator lens group, and 403 denotes a focusing lens group. Reference numeral 404 denotes an optical low-pass filter. An imaging unit 411 is disposed at the focal position (scheduled imaging plane) of the photographing optical system 400. This is a photoelectric conversion means such as a two-dimensional CCD comprising a plurality of photoelectric conversion units for converting irradiated light energy into charges, a charge storage unit for storing the charges, and a charge transfer unit for transferring the charges and sending them to the outside. Is used.

  Reference numeral 421 denotes a display such as a liquid crystal display, which displays the subject image acquired by the imaging unit 411 and the operation status of the optical device. Reference numeral 422 denotes a group of operation switches including a zoom switch, a shooting preparation switch, a shooting start switch, and a shooting condition switch for setting a shutter speed. Reference numeral 423 denotes an actuator that performs focus driving to adjust the focus state of the photographing optical system 400 and to drive other members.

  The CPU 431 calculates whether the captured average density is equal to the numerical value corresponding to the appropriate exposure stored in itself, and if there is a difference, the absolute sign of the difference is calculated. Depending on the absolute value, the aperture opening is changed, or the charge accumulation time in the imaging means 411 is changed. When moving the diaphragm, the diaphragm blade driving lever 103 is rotated about the rotation center 103a by the diaphragm driving circuit 432, so that the diaphragm blades 101 and 102 slide up and down. As a result, the size of the optical path hole 106 that is the opening changes. Thus, the optimum exposure can be obtained by changing the aperture area or the charge accumulation time.

  The image of the subject imaged on the image pickup means 411 at the optimum exposure is converted into an electric signal as a charge amount for each pixel according to the intensity of the brightness, amplified by the amplifier circuit 441, and then the camera signal. The processing circuit 442 performs processing such as predetermined γ correction. Note that this processing may be performed by digital signal processing after A / D conversion. The video signal thus created is recorded by the recorder 443.

  Next, the present invention will be described more specifically with reference to examples and comparative examples. In the text, “%” is based on mass.

<Example 1>
Silicon rubber (silicone TPR6712 manufactured by Toshiba Silicone Co., Ltd., catalyst CM670) was applied onto a silicon substrate using a spin coater to form a release layer, which was used as a transfer substrate.

  Next, a solution of polyvinyl acetal (Sekisui Chemical Co., Ltd., SREC K KW-1) was applied onto the release layer formed above using a wire bar, and 100 ° C., 5 ° C. in a hot air drying oven. Drying was performed under the condition of minutes. The ink receiving layer thus prepared had a thickness of 7 μm.

  Next, a bubble jet (registered trademark) type ink jet printer using an electrothermal transducer as an energy generating element; a BJ F930 ink tank manufactured by Canon Inc. is filled with colored ink having the following composition, and is prepared as described above. Applied to the ink receiving layer. At that time, an optical density of 0.5 (transmittance of 32%) was applied so as to be a uniform density, and the colored layer was further dried at 180 ° C. for 2 minutes to perform water resistance treatment of the colored layer.

・ Black pigment: Water dispersible carbon black 4%
(Cabot IJX-102B)
・ Ethylene glycol 5%
・ Diethylene glycol 5%
・ Isopropyl alcohol 2%
・ Acetylenol EH 1%
(Made by Kawaken Fine Chemicals)
・ Ion exchange water 83%

  Next, an epoxy UV curing resin was used on the colored layer formed by applying and receiving the colored ink, and coating was performed using a spin coater to provide an adhesive layer. Next, a polyethylene terephthalate film as a first transparent substrate is closely attached to the adhesive layer provided above so as not to contain air bubbles, and further light is applied under conditions of 200 mW and 60 seconds using a high-pressure mercury lamp. It was cured and cured by irradiation.

  Next, what was formed above was peeled from the silicon substrate. At this time, peeling was performed between the release layer and the colored layer due to the difference in adhesion between the release layer and the silicon substrate and the adhesive layer. Next, on the polyethylene terephthalate film as the second transparent substrate, the epoxy-based UV curable resin used as the adhesive layer is applied using a spin coater to form a second adhesive layer, and there The release surface of what was formed above was adhered to a polyethylene terephthalate film as a second transparent substrate.

  The light quantity adjusting member according to the present invention produced as described above was placed in front of the photographing lens of a digital camera Power Shot G1 manufactured by Canon Inc., and a resolution chart for an ISO standard electronic still camera was photographed. The exposure control mode uses aperture priority AE by opening the aperture so that proper exposure can be obtained regardless of the presence or absence of the light amount adjusting member. A black and white bar chart (spatial frequency on the image plane: 14.5 line pairs / mm) was cut out from the photographed image, and the difference between the level of the white portion and the level of the black portion of the image was obtained and used as the evaluation contrast. Next, the light amount adjusting member was removed and the same photographing was performed to obtain the difference between the white level and the black level of the image, and this was used as the reference contrast.

  The ratio of the evaluation contrast to the reference contrast obtained in this way was obtained and defined as the filter contrast. In this example, this value was 0.93. The allowable lower limit value of the filter contrast varies depending on the usage and price range of the imaging apparatus, but it has been found that 0.9 or more is preferable for the wide-class imaging apparatus and 0.92 or more for the high-class class. Therefore, it can be seen that the filter contrast value 0.93 of the light quantity adjusting member of the present invention is sufficiently high performance. Further, as a result of measuring the wavefront aberration of the light amount adjusting member prepared as described above with a laser interferometer, it was found that the flatness of the entire surface was very high.

  Furthermore, after the light quantity adjusting member of the present invention produced as described above was left for 100 hours in an environment of a temperature of 60 ° C. and a relative humidity of 90%, the wavefront aberration was measured by a laser interferometer. As a result, since the wavefront aberration measurement result is not significantly changed as compared with that before standing at high temperature and high humidity, it was found that the phenomenon of swelling of the end face of the light amount adjusting member and the increase of the film thickness is small.

<Example 2>
In the same manner as in Example 1, silicon rubber (silicone TPR6712 manufactured by Toshiba Silicone Co., Ltd., catalyst CM670) was applied onto a silicon substrate using a spin coater to form a release layer, did.

  Next, a 10% aqueous solution with a solid content concentration was prepared using polyvinyl alcohol (Nippon Synthetic Chemical Co., Ltd. Gohsenol GM-14L). The obtained coating liquid was coated on the release layer using a wire bar, and dried in a hot air drying oven at 100 ° C. for 5 minutes. The ink receiving layer thus prepared had a thickness of 7 μm.

  Next, a bubble jet (registered trademark) type ink jet printer using an electrothermal transducer as an energy generating element; a Canon ink BJ F930 ink tank filled with a colored ink having the following composition and prepared as described above On the ink receiving layer, an optical density of 0.5 (transmittance of 32%) was applied so as to obtain a uniform density.

・ Black dye food black 2 5%
・ Ethylene glycol 5%
・ Diethylene glycol 5%
・ Isopropyl alcohol 2%
・ Acetylenol EH 1%
(Made by Kawaken Fine Chemicals)
・ Ion exchange water 82%

  Next, a part of the colored layer formed above was irradiated with a YAG laser beam, and a part of the colored layer was removed. At that time, the laser beam diameter was adjusted so that the removal width of the colored layer was 50 to 150 μm. When a part of the colored layer is removed, a part of the release layer may also be removed, but there is no real harm when the depth to be removed is shallow.

  Next, an epoxy UV curable resin was used as a material for forming the adhesive layer on the colored layer formed by applying and receiving the colored ink, and coating was performed using a spin coater to provide an adhesive layer. Next, a polyethylene terephthalate film as a first transparent substrate is closely attached to the adhesive layer provided above so as not to contain air bubbles, and further light is applied under conditions of 200 mW and 60 seconds using a high-pressure mercury lamp. It was cured and adhered by irradiation.

  Next, what was formed above was peeled from the silicon substrate. At this time, peeling was performed between the release layer and the colored layer due to the difference in adhesiveness between the silicon substrate of the release layer and the colored layer. Next, on the polyethylene terephthalate film as the second transparent substrate, the epoxy-based UV curable resin used as the adhesive layer is applied using a spin coater to form a second adhesive layer, and there The light-adjusting member is bonded to the polyethylene terephthalate film as the second transparent substrate, and cut at a portion where the colored layer is not present, and the colored layer is not exposed to the outside air. Created.

  The contrast value of the light amount adjusting member of the present invention produced as described above was determined in the same manner as in Example 1. As a result, it was found that the contrast value was 0.93, which was high performance as in Example 1. Further, as a result of measuring the wavefront aberration of the light amount adjusting member prepared as described above with a laser interferometer, it was found that the flatness of the entire surface was very high.

  Furthermore, after the light quantity adjusting member of the present invention produced as described above was left for 100 hours in an environment of a temperature of 60 ° C. and a relative humidity of 90%, the wavefront aberration was measured by a laser interferometer. As a result, it was found that the phenomenon of swelling of the end face of the light amount adjusting member and the increase in the film thickness did not occur because there was no change in the wavefront aberration measurement result as compared with that before standing at high temperature and high humidity.

<Example 3>
A light amount adjusting member was produced in the same manner as in Example 1. However, the application of the colored ink was not made uniform over the entire surface of the ink receiving layer, but a density gradient was given stepwise to obtain a gradation pattern as shown in FIG. The light quantity adjusting member thus prepared was evaluated by obtaining the contrast value in the same manner as in Example 1. As a result, the obtained contrast value was as high as 0.93. Further, as a result of measuring the wavefront aberration of the light amount adjusting member prepared as described above with a laser interferometer, it was found that the flatness of the entire surface was very high.

  Furthermore, after the light quantity adjusting member of the present invention produced as described above was left for 100 hours in an environment of a temperature of 60 ° C. and a relative humidity of 90%, the wavefront aberration was measured by a laser interferometer. As a result, it was found that the wavefront aberration measurement results were not significantly changed compared with those before being left at a high temperature and high humidity, so that the phenomenon of swelling of the end face of the light amount adjusting member and the increase in film thickness was small.

<Example 4>
A light amount adjusting member was prepared in the same manner as in Example 1. However, the application of the colored ink was not uniform, and a gradation pattern was formed with a continuous density gradient, and the gradation level was unclear. The light intensity adjusting member thus prepared was evaluated by obtaining the contrast value in the same manner as in Example 1. As a result, the obtained contrast value was 0.93, which was high performance. Further, as a result of measuring the wavefront aberration of the light amount adjusting member prepared as described above with a laser interferometer, it was found that the flatness of the entire surface was very high.

  Furthermore, after the light quantity adjusting member of the present invention produced as described above was left for 100 hours in an environment of a temperature of 60 ° C. and a relative humidity of 90%, the wavefront aberration was measured by a laser interferometer. As a result, it was found that the wavefront aberration measurement results were not significantly changed compared with those before being left at a high temperature and high humidity, so that the phenomenon of swelling of the end face of the light amount adjusting member and the increase in film thickness was small.

<Comparative Example 1>
In Example 1, the ink receiving layer was coated on the entire surface of a polyethylene terephthalate film as a transparent substrate, dried in a hot air drying oven at 100 ° C. for 5 minutes, and exactly the same as in Example 1. After coloring, an epoxy UV curable resin was used on the colored layer, and coating was performed using a spin coater. This was cut out into a size of 10 mm × 10 mm to prepare a light amount adjusting member in which the colored layer was exposed to the outside air.

  The contrast value of the light amount adjusting member produced as described above was obtained in the same manner as in Example 1. As a result, it was found that the contrast value was 0.93, which was high performance as in Example 1. However, as a result of measuring the wavefront aberration of the light amount adjusting member prepared as described above with a laser interferometer, it was found that there was undulation over the entire surface.

  Further, after the light quantity adjusting member produced as described above was left for 100 hours in an environment of a temperature of 60 ° C. and a relative humidity of 90%, the wavefront aberration was measured by a laser interferometer. As a result, it was found that the wavefront aberration increased over the entire circumference of the width of 1 mm from the end face, and the wavefront aberration increased by a maximum of about λ / 2 at the end face as compared to before leaving at high temperature and high humidity. This is presumably because the colored layer is exposed at the end face of the light amount adjusting member, and moisture in the air enters from the exposed portion to cause a swelling phenomenon and increase the film thickness of the peripheral portion.

  According to the present invention, there are provided a light amount adjusting member, a manufacturing method thereof, a light amount adjusting device, and a photographing device that are very simple operation, low in yield, excellent in flatness, long-term reliability, and particularly excellent in moisture resistance. Is done. In addition, according to the present invention, it is possible to simply provide a light amount adjusting member having a density distribution continuously or stepwise, which is extremely difficult in other manufacturing methods.

Explanatory drawing of the manufacturing method of the light quantity adjustment member of this invention. Explanatory drawing of the manufacturing method of the light quantity adjustment member of this invention. Explanatory drawing of an example of the light quantity adjustment member of this invention. Explanatory drawing of the light quantity adjustment apparatus of this invention. The block diagram of the imaging device incorporating the light quantity adjustment apparatus of this invention. Explanatory drawing of the light quantity adjustment member which has a concentration gradient in steps.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100: Light quantity adjustment apparatus 101, 102: Diaphragm blade 103: Diaphragm blade drive lever 101P, 102P: Light quantity adjustment member 101Q, 102Q: Light blocking member 105: Guide pin 106: Optical path hole 111 of base plate: Transparent base material 112: Colored layer 400: photographing optical system 401: first lens group 402: second lens group 403: third lens group 404: optical low-pass filter 411: imaging means 421: display 422: operation switch group 423: actuator 431: CPU
432: Aperture drive circuit 433: Image pickup means drive circuit 441: Amplifier circuit 442: Camera signal processing circuit 443: Recorder

Claims (13)

  A light quantity adjusting member comprising a pair of transparent base materials and a colored layer sandwiched between the pair of transparent base materials.   The light quantity adjusting member according to claim 1, wherein a transparent adhesive layer is formed between the pair of transparent base materials and the colored layer.   The light quantity adjusting member according to claim 2, wherein an end surface of the colored layer is sealed by the adhesive layer.   The light quantity adjusting member according to claim 1, wherein the colored layer has a concentration distribution continuously or stepwise.   A step of providing a layer made of a material capable of absorbing a colored liquid on a transfer substrate, a step of forming a colored layer by applying a colored liquid containing a coloring material to the layer by a liquid jet recording method, and the coloring A method for producing a light amount adjusting member, comprising: transferring a layer onto a first transparent substrate; and laminating a second transparent substrate on a release surface of the transferred colored layer.   The method for producing a light amount adjusting member according to claim 5, wherein the transfer substrate has a release layer.   The manufacturing method of the light quantity adjustment member of Claim 5 or 6 which transfers the said colored layer on a 1st transparent base material through the transparent contact bonding layer provided on this colored layer.   The manufacturing method of the light quantity adjustment member of any one of Claims 5-7 which provides a coloring liquid so that the said colored layer may have density distribution continuously or in steps.   The said adhesive layer is formed so that the end surface of the said colored layer may be sealed, and the partial change of the optical path length which arises by the moisture absorption of the said colored layer is prevented. Manufacturing method of the light quantity adjusting member.   The manufacturing method of the light quantity adjustment member of Claim 9 which removes a part of said colored layer and seals the end surface of a colored layer with the said contact bonding layer.   A light quantity adjusting member manufactured by the manufacturing method according to claim 5.   A light amount adjusting device comprising the light amount adjusting member according to claim 11. A light amount adjusting device according to claim 12, a photographing optical system for forming a subject image, an imaging means for photoelectrically converting the formed subject image, and a recording means for recording the photoelectrically converted signal, A photographing apparatus, wherein the light amount adjusting device is disposed in the photographing optical system.

Images