Abstract: An image that has been displayed on the display screen of an image generator is first passed through a projection lens section consisting of a front group and a rear group. Next after being reflected on the reflecting surface of a free-form surface mirror, the image is further reflected by a planar reflecting mirror and then obliquely projected from the lower section of a projection screen onto the screen. The front group of the projection lens section is provided for enlarging the image. In order to correct aberration due to oblique projection onto the projection screen, the rear group uses a free-form surface lens that forms a concave shape with respect to the exit side of light from the lens. The free-form surface mirror corrects trapezoidal distortion due to oblique projection onto the projection screen.

Abstract: In a Fresnel screen for displaying an image, comprising, a screen surface, and a reverse surface opposite to the screen surface in a thickness direction of the screen to be prevented from facing to the viewer, the Fresnel screen has first prism surfaces extending to have respective longitudinal arc-shapes juxtaposed with each other as seen in the thickness direction to deflect light beams for forming the image in at least one of directions perpendicular to each other as seen in the thickness direction, and second prism surfaces extending to have respective longitudinal shapes juxtaposed with each other as seen in the thickness direction to deflect at least a part of the light beams in at least one of the directions perpendicular to each other as seen in the thickness direction.

Abstract: A photomask blank is prepared by forming a light-absorbing film on a transparent substrate, and irradiating the light-absorbing film with light from a flash lamp at an energy density of 3 to 40 J/cm2. A photomask is prepared by forming a resist pattern on the photomask blank by photolithography, etching away those portions of the light-absorbing film which are not covered with the resist pattern, and removing the resist.

Abstract: A film-depositing target for use in the manufacture of a halftone phase shift mask blank includes a transparent substrate and a translucent film of one or more layers having a controlled phase and transmittance, at least one layer of the translucent film including silicon, molybdenum and zirconium at the same time as constituent elements, and at least two elements, zirconium and molybdenum in a molar ratio Zr/Mo between 0.05 and 5.

Abstract: The signal processing circuit includes: a buffer memory for temporarily storing a shot image; and a moving-picture detection device for detecting whether or not the shot image is a moving picture. Whether to store the shot image in the buffer memory as a moving memory, as a still picture, or as both a moving picture and a still picture is determined according to the detection result of the moving-picture detection device.

Abstract: In the image display device, a projection lens including a plurality of lenses for enlarging an image from an image display element is constituted of a front group and a rear group. The rear group includes at least one free-shaped-surface lens including a surface having a rotationally asymmetrical shape. Furthermore, the device includes at least one free-shaped-surface mirror having a rotationally asymmetrical reflection surface. Accordingly, a set can be formed to be compact while correcting trapezoidal distortion and aberration.

Abstract: The present invention provides a technique suitable for making a set more compact by realizing reduction in height and reduction in depth. An image display apparatus of the present invention includes a reflecting mirror (4) for reflecting the image sent from a projection lens (2), and guiding the image to a transmissive screen (3). The reflecting-mirror (4) includes a planar mirror section (4a) for reflecting, of the entire image exiting the projection lens (2), only image portions projected onto the upper section of the transmissive screen (3), and a Fresnel mirror section (4b) with multiple reflective prisms for reflecting only image portions projected onto the lower section of the screen (3).

Abstract: The present invention provides a technology suitable for shortening a depth of a image display apparatus while obtaining a picture of high quality. According to the invention, a total reflection prism portion is provided on a side of a Fresnel lens sheet toward a picture source. The total reflection prism portion reflects an incident light to a direction toward an optic axial center of the Fresnel lens sheet to have the same outgoing. On the other hand, a first refractive prism portion, by which light of a predetermined incident angle or less is refracted to outgo to a direction along an optical axis of the Fresnel lens sheet, and a second refractive prism portion, by which light reflected to the direction toward the optic axial center of the Fresnel lens sheet is changed to the direction along the optical axis.

Abstract: Images that are bright even on the periphery of a transmissive screen are obtained by reducing reflection loss of the screen when the screen incident angle of the image light entering the upper left and right ends of the screen increases. Incident-side prisms (10), each having at least a plane-of-incidence (c) onto which light comes in, an exit face (d) from which the light that has come in from the plane-of-incidence exits after being refracted, and a refractive face (e) on which the light that has exited from the exit face is refracted and then guided to the image-viewing side of the Fresnel lens sheet (6), are provided in the range where the incident angle of the incoming light becomes equal to or greater than approximately 40 degrees.

Abstract: In preparing a halftone phase shift mask blank, a metal and silicon-containing compound film serving as a halftone phase shift film is formed on a transparent substrate by a co-sputtering process including the steps of disposing a metal-containing target and a silicon target in a chamber, feeding sputtering gases into the chamber, and applying electric powers across both the targets at the same time. The sputtered region area of the metal-containing target is smaller than the sputtered region area of the silicon target.

Abstract: In a halftone phase shift mask blank comprising a halftone phase shift film on a substrate which is transparent to exposure light, the halftone phase shift film comprises a metal, silicon, and optionally oxygen and nitrogen. The halftone phase shift film experiences a phase difference change of up to 1 deg. and a transmittance change of up to 0.2% before and after it is exposed to light in a cumulative dose of 1 kJ/cm2. The halftone phase shift film has excellent resistance to exposure light, specifically high-energy exposure light of short wavelength such as ArF or F2 laser beam (193 or 157 nm).

Abstract: An image display apparatus includes an image generation source, optics for projecting in an enlarged form the image generated by the image generation source, and a transmissive screen for displaying the image projected from said optics. The transmissive screen includes a Fresnel lens sheet disposed at an image generation source side, and a diffusing sheet disposed at an image-watching side in order to diffuse image light at least in a horizontal direction of the screen. The Fresnel lens sheet has a plurality of entrance-side prisms formed at the image generation source side, and a plurality of exit-side prisms formed at the image-watching side, and the Fresnel lens sheet emits lights in a first direction and a second direction. The first direction is almost parallel to a central axis of the Fresnel lens sheet, and the second direction extends toward the central axis.

Abstract: The present invention provides a screen suitable for reducing the longitudinal dimension of a set. The present invention includes two prism sections. One is a totally reflective prism section (10) provided at the image generation source side of a Fresnel lens sheet (6). The other is a refractive prism section (11) provided at the image-watching side of the Fresnel lens sheet. The refractive prism section (11) includes a refractive face (e) for refracting incident light and making the light exit toward the image-watching side, a plane (f) approximately parallel to the principal plane of the Fresnel lens sheet, and a connection face (g) for continuously forming the face (e) and the plane (f).

Abstract: The present invention provides a technology that makes it possible to display high-quality images by reducing a reflection loss of the image light entering the upper left and right ends of a transmissive screen. At the image generation source side of the Fresnel lens sheet, a totally reflective prism section (10) is provided that totally reflects incident rays of light and causes the light to exit toward the image-watching side. At the image-watching side of the Fresnel lens sheet (6), a refractive prism section (11) is also provided that refracts the light entering from the totally reflective prism section (10) and causes the light to exit toward the image-watching side. The refractive prism section (11) has a roughed refractive face.

Abstract: A photomask blank comprising a multilayer film including at least four layers of different compositions, wherein the interface between the layers is moderately graded in composition; a phase shift mask blank comprising a phase shift film of at least two layers including a surface layer of a composition based on a zirconium silicide compound and a substrate adjacent layer of a composition based on a molybdenum silicide compound, and a further layer between one layer and another layer of a different composition, the further layer having a composition moderately graded from that of the one layer to that of the other layer; a phase shift mask blank comprising a phase shift film including a plurality of layers containing a metal and silicon in different compositional ratios which are stacked in such order that a layer having a higher etching rate is on the substrate side and a layer having a lower etching rate is on the surface side.

Abstract: In a phase shift mask blank comprising a phase shift multilayer film on a substrate, the phase shift multilayer film consists of at least one layer of light absorption function film and at least one layer of phase shift function film, and the light absorption function film has an extinction coefficient k which increases as the wavelength changes from 157 nm to 260 nm, and has a thickness of up to 15 nm. The phase shift mask blank has minimized wavelength dependency of transmittance and can be processed with a single dry etching gas.

Abstract: An opaque area is formed in a sidewall portion of a susceptor by stacking a material that is transparent to flash light and a material that is opaque to the flash light to form the sidewall portion or coating a surface of the opaque material with the transparent material. A top surface of the opaque area in the sidewall portion of the susceptor is designed to have a predetermined positional relationship with a top surface of a substrate; the top surface of the opaque area is set at the same position as that of the top surface of the substrate or higher than the top surface of the substrate by a predetermined height. Thus, obliquely incident flash light is absorbed or irregularly reflected by the opaque quartz portion, surrounding an excavated portion of the susceptor.

Abstract: There is disclosed a method of producing a phase shift mask blank wherein the method includes at least a step of forming one or more layers of phase shift films on a substrate by a sputtering method, and in the step, the phase shift films are formed by the sputtering method while simultaneously discharging plural targets having different compositions. Thereby, a phase shift mask blank having a desired composition and quality, in particular, having a phase shift film with few defects can be easily produced.

Abstract: A photomask blank to be used as a material for a photomask is provided with a mask pattern having a transparent area and an effectively opaque area to exposure light on a transparent substrate. On the transparent board, one or more layers of light shielding films are formed with or without other film (A) in between, at least one layer (B) which constitutes the light shielding film includes silicon and a transition metal as main component, and a molar ratio of silicon to the transition metal is silicon:metal=4-15:1 (atomic ratio). The photomask provided with the mask pattern having the transparent area and the effectively opaque area to exposure light on the transparent board is also provided.

Abstract: A photomask blank comprising a multilayer film including at least four layers of different compositions, wherein the interface between the layers is moderately graded in composition; a phase shift mask blank comprising a phase shift film of at least two layers including a surface layer of a composition based on a zirconium silicide compound and a substrate adjacent layer of a composition based on a molybdenum silicide compound, and a further layer between one layer and another layer of a different composition, the further layer having a composition moderately graded from that of the one layer to that of the other layer; a phase shift mask blank comprising a phase shift film including a plurality of layers containing a metal and silicon in different compositional ratios which are stacked in such order that a layer having a higher etching rate is on the substrate side and a layer having a lower etching rate is on the surface side.