Abstract: A polarizing conversion element array (500) of a polarization converter (414) has two polarizing conversion elements (510) provided with a polarization separating film (511) for separating a light beam into two linearly polarization beams and a reflecting film (512) that reflects one of the linearly polarization beams separated by the polarization separating film (511) in an alternate manner, the two polarizing conversion elements (510) being arranged so that the respective polarization separating films (511) and the reflecting films (512) are opposed, the polarization converter (414) being constructed by adhering a retardation plate (600) on a light-irradiation side of the polarizing conversion element array (500) stretching over the two polarizing conversion elements (510).

Abstract: A polarization converter (414) has polarizing conversion element body (414B) including: a polarization separating film (511) that separates an incident light into two linearly polarization beam; a reflecting film (512) alternately disposed between the polarization separating films (511), the reflecting film reflecting a linearly polarization beam reflected by the polarization separating film (511); a sheet glass (513) provided with the polarization separating film (511) and the reflecting film (512); and a retardation plate (600) that converts a polarization axis of the linearly polarization beam transmitted through the polarization separating film (511), a fixing frame (414A) that shields incident light beam on a position on the light-incident side of the polarizing conversion element body (414B) not opposing to the polarizing conversion element body (414B), the fixing frame (414A) having a holder that holds an end of the polarizing conversion element body (414B) and a fixing portion to be fixed to an inner

Abstract: A distributed amplifier having a plurality of cascode amplifying circuits, and which causes little deterioration of the output waveform. In a preferred embodiment, the source potentials of the source-grounded transistors of the respective amplifying circuits are set individually. The source potentials of none or one or more of the source-grounded transistors are set at +0.8 volts, and the source potentials of the remaining source-grounded transistors are set at zero volts. The voltage gain of the source-grounded transistors whose source potential is +0.8 volts is zero, so that these source-grounded transistors do not contribute to the voltage gain of the amplifier as a whole. The source-grounded transistors whose source potential is zero volts contribute to the voltage gain, and output an amplified signal with a good waveform. The magnitude of the voltage gain can be adjusted by setting the number of source-grounded transistors whose source potential is zero volts.

Abstract: An optical modulation device is presented having a distance Wp from the end of an opposite substrate to the inner peripheral edge of a cover portion in a frame being set to be smaller than the distance W1 from the end of the opposite substrate to the inner peripheral edge of a first light-shielding portion (Wp<W1). Therefore, there is no fear that incident light from outside of the inner peripheral edge of the cover portion may be blocked by the cover portion, so that incident light may reliably enter the entire image area. This arrangement makes it possible to prevent the peripheral portion of a projection image from becoming dark, and thereby improve the quality of the projection image.

Abstract: The present invention provides a technique that reduces color non-uniformity in a color image projected and displayed by a projector. The projector that projects and displays the color image includes an illumination optical system, a color light separation optical system, first through third electro-optical devices, a color light synthesizing optical system, and a projection optical system. The projector generally has one or a plurality of light bundle adjustment optical systems provided in one or some of three optical paths, which respectively connect the color light separation optical system with the first through the third electro-optical devices. Each light bundle adjustment optical system regulates size of a light bundle of a selected color light.

Abstract: The illumination system comprises a light source; a first lens array of small lenses for dividing light from the light source into a plurality of light beams; and a second lens array of small lenses corresponding to the small lenses of the first lens array. The second lens array is located near where the plurality of light beams from the first lens array are converged. Each small lens of the second lens array has an outer shape of a non-rectangular polygon which is related to a profile of the light converged by a corresponding small lens of the first lens array. The second lens array may have a flat portion provided between the columns of the small lenses.

Abstract: In a second lens array 130A of an illumination optical system according to the present invention, the position of curved faces of third minute lenses 132Ab is displaced from the position of curved faces of second minute lenses 132Aa. Such displacement makes the size of a first region W1 on an illuminating area LA, which is irradiated with light transmitted by polarizing separation films 142, substantially equal to the size of a second region W2 on the illuminating area LA, which is irradiated with light reflected by the polarizing separation films 142 and reflection films 144. This arrangement effectively prevents the significant reduction of the illuminating efficiency occurring in a prior art illumination optical system that utilizes a polarization conversion optical system.

Abstract: A device for controlling power supply to subscribers in a digital subscriber-switch board includes subscriber-line circuits which supply power to the subscribers, and a carrier-detection unit which is connected to a communication path to detect a carrier signal of a modem once the communication path is established between a caller and a receiver, the caller being one of the subscribers, wherein one of the subscriber-line circuits corresponding to the one of the subscribers is controlled to suspend power supply to the one of the subscribers when the carrier-detection unit detects the carrier signal on the communication path.

Abstract: The distance Wp from the end of a opposite substrate 400 to the inner peripheral edge of a cover portion 95 in a frame 91 is set to be smaller than the distance W1 from the end of the opposite substrate 400 to the inner peripheral edge of a first light-shielding portion 31 (Wp<W1). Therefore, there is no fear that incident light, which is incident from the outside (&thgr;o side) of the inner peripheral edge of the cover portion 95 may be blocked by the cover portion 95, and incident light reliably enters the entire image area, which makes it possible to prevent the peripheral portion of a projection image from becoming dark, and to thereby improve the quality of the projection image.

Abstract: An optical modulation device is presented having a distance Wp from the end of an opposite substrate to the inner peripheral edge of a cover portion in a frame being set to be smaller than the distance W1 from the end of the opposite substrate to the inner peripheral edge of a first light-shielding portion (Wp<W1). Therefore, there is no fear that incident light from outside of the inner peripheral edge of the cover portion may be blocked by the cover portion, so that incident light may reliably enter the entire image area. This arrangement makes it possible to prevent the peripheral portion of a projection image from becoming dark, and thereby improve the quality of the projection image.

Abstract: A projector includes a light source, a beam splitter for splitting a light irradiated from the light source into a plurality of partial light beams, a polarization converter for converting the light beam irradiated from the beam splitter into a predetermined linear polarization light beam, and a lens array for transmitting the plurality of partial light beams irradiated from the polarization converter to a light modulator, where the polarization converter and the lens array are integrated by a holding frame and are fixed to a fixing portion of a support, so that the polarization converter and the lens array can be attached to the fixing portion of the support while adjusting position of the integrated component relative to the fixing portion, thus reducing trouble for position adjustment.

Abstract: In a second lens array 130A of an illumination optical system according to the present invention, the position of curved faces of third minute lenses 132Ab is displaced from the position of curved faces of second minute lenses 132Aa. Such displacement makes the size of a first region W1 on an illuminating area LA, which is irradiated with light transmitted by polarizing separation films 142, substantially equal to the size of a second region W2 on the illuminating area LA, which is irradiated with light reflected by the polarizing separation films 142 and reflection films 144.This arrangement effectively prevents the significant reduction of the illuminating efficiency occurring in a prior art illumination optical system that utilizes a polarization conversion optical system.

Abstract: The present invention provides a technique that reduces color non-uniformity in a color image projected and displayed by a projector. The projector that projects and displays the color image includes an illumination optical system, a color light separation optical system, first through third electro-optical devices, a color light synthesizing optical system, and a projection optical system. The projector generally has one or a plurality of light bundle adjustment optical systems provided in one or some of three optical paths, which respectively connect the color light separation optical system with the first through the third electro-optical devices. Each light bundle adjustment optical system regulates size of a light bundle of a selected color light.

Abstract: In a projection display device 1, emergent light from an illumination optical system 80 is diffused by microlenses 101 provided in a liquid crystal light valve 100R. Emergent light from the liquid crystal light valve 100R diffused by these microlenses 101 is efficiently drawn into a projection optical system 60 whose f-number is set to be less than the f-number of the illumination optical system 80. As a result, it is possible to prevent light utilization efficiency from being deteriorated due to light diffusion by the microlenses 101. Consequently, it is possible to obtain a bright projection image in a projection display device in which a liquid crystal light valve having microlenses is incorporated.

Abstract: A coplanar transmission line of the present invention comprises a substrate 10, earth-connected conductors 14, 16 formed on the substrate 10, and a center conductor 12 formed between the earth-connected conductors 14, 16. The center conductor 12 includes a lower center conductor 12a and an upper center conductor 12b formed on the lower center conductor 12a. An edge of the upper center conductor 12b is set-back from an edge of the lower center conductor 12a.

Abstract: An illumination system includes a light source and a dividing and superimposing section that divides a light flux emitted from the light source into a plurality of partial light fluxes and causes the plurality of partal light fluxes to be substantially superimposed on an illumination area, so as to enable a light-entering face of a specific optical apparatus to be illuminated as the illumination area. The dividing and superimposing section includes a light flux contraction section having the function of an afocal optical system that changes an incident light flux to an emitting light flux, the emitting light flux having a width narrower than the incident light flux. The afocal optical system accordingly decreases the incident angle of the plurality of partial light fluxes into the illumination area to be superimposed on the illumination area.

Abstract: The invention prevents deterioration of the image quality caused by dust adhering to the surface of a liquid crystal device. The invention is a liquid crystal device that includes an emergent-side substrate section, an incident-side substrate section disposed opposing the emergent-side substrate section, and a liquid crystal layer sandwiched between the emergent-side substrate section and the incident-side substrate section. The incident-side substrate section includes an incident-side substrate, an electrode that drives the liquid crystal layer formed on the incident-side substrate, and a micro-lens array disposed toward an incident side of the liquid crystal device relative to the incident-side substrate and having a plurality of micro-lenses that condense light beams onto a plurality of pixels. A thickness Ti of the incident side-substrate section along a direction of travel of a light beam is larger than a thickness To of the emergent side-substrate section along the direction of travel of the light beam.

Abstract: A projection-type display apparatus in accordance with the invention reduces the margin formed around the image forming range of the light valves, and forms a bright projected image. Emitted light from a light source lamp unit of a projection-type display apparatus illuminates liquid crystal light valves of each color via an integrator optical system. First and second lens plates of an integrator optical system that serves as a uniform illuminating optical system are disposed such that the attachment position thereof is capable of fine adjustment in a direction vertical to the optical axis. By performing fine adjustment of the attachment position of these, the forming position of the illumination range B can be adjusted to include the image forming range A of the liquid crystal light valves. Accordingly, there is no need to provide a wide margin around the image forming range A, taking shifting of the forming position of the illumination range B into consideration.

Abstract: A liquid crystal device that modulates light in accordance with supplied image information comprises a plurality of pixels arranged in a matrix, each pixel having an opening to allow passage of light, and an array of micro-lenses arranged in a matrix that divides illumination light into a plurality of partial light beams and converges the light beams to a light incidence plane of the pixels. In the liquid crystal device, the characteristics of the micro-lenses are adjusted to increase a proportion of light exiting from the opening of each pixel substantially parallel to a clear viewing direction of the liquid crystal device compared to a proportion of light parallel to other directions. Each micro-lens is positioned so that a line connecting the optical center of the micro-lens to the center of the incident surface of the corresponding pixel is substantially parallel to the clear viewing direction.

Abstract: An output light from an light source lamp unit 8 in a projection-type display apparatus illuminates liquid-crystal light valves 925R, 925G and 925B for three colors via an integrator optical system 923. A superimposing lens 930 that is a component of the integrator optical system 923 as a uniform illumination optical system is arranged such that the mounting position of the superimposing lens 930 is fine-adjustable in a direction orthogonal to an optical axis 1a. By fine-adjusting the mounting position of the superimposing lens 930, the position of an illumination area B is adjusted such that the illumination area includes the image forming area A of the liquid-crystal light valve. It is not necessary to assure a wide margin around the image forming area A to cover the offset of the position of the illumination area B. As a result, the utilization of illumination light is heightened and a bright projected image results.