Abstract: Aspects of the invention can provide a projector that includes three optical modulators which modulate respectively red light, green light, and blue light, a color-synthetic optical system which synthesizes the light modulated by the three optical modulators, and a projection optical system which projects the light synthesized by the color-synthetic optical system. The color-synthetic optical system can include a first reflection film that reflects the green light, and a second reflection film that reflects the blue light, the first reflection film and the second reflection film are arranged in the shape of an X character, and a wavelength in which a reflectance factor of the first reflection film comes to 50% can be longer than a wavelength in which a reflectance factor of the second reflection film comes to 50%.

Abstract: Aspects of the invention can provide a projector that can include an illumination device that emits an illumination light, a color separation system that separates the illumination light emitted from the illumination device into a blue light, a red light, and a green light, and guides the blue light and the red light, respectively, to first and second optical paths, and the green light to a third optical path in which a relay system is provided, first through third light modulation devices that are provided, respectively, in the first through third optical paths, and illuminated by the blue light, the red light, and the green light, respectively, a light combining system that can have a first dichroic filter reflecting one of the blue light and the red light, and a second dichroic filter reflecting the green light which are placed in a crossed state, and that can combine image lights of respective colors exiting from the first through third light modulation devices to go incident on the first and second dichr

Abstract: Aspects of the invention can provide a projector can include an illumination device that outputs illumination light, a color separation system that divides the illumination light output from the illumination device into blue light, red light, and green light and guides the blue light, red light, and green light to first to third optical paths, respectively, and first to third light modulation devices disposed in the first to third optical paths to be illuminated by the blue light, red light, and green light. In the projector, a distance from the illumination device to the third optical modulation device can be longer than a distance from the illumination device to the first optical modulation device and a distance from the illumination device to the second optical modulation device, a relay system having a first lens disposed at the light incident side, a second lens disposed at the light exit side, and a third lens disposed between the first and second lenses can be provided in the third optical path.

Abstract: To provide a projector that hardly causes deterioration of an image resulted from stray light. A neutral density filter, of which posture can be fine-adjusted by a posture regulating mechanism, is placed in a space between a second dichroic mirror and a liquid crystal light valve. Thus, it is possible to remove stray light, corresponding to condensed light resulted from multi-pass through a field lens or the like, to the outside of a light path by merely tilting the neutral density filter adequately. It is thus possible to project an image having homogeneous brightness (illuminance at the white level) across the entire screen, which in turn makes it possible to project an image having no irregularities in color across the entire screen.

Abstract: A water purification process comprises applying electrical energy to water to be treated in a treatment chamber having a cathode and an anode opposing each other and deactivates or destroys microorganisms in the water. Water in the vicinity of the anode is caused to flow away from the anode by subjecting the water and/or the anode to vibration. The water purification apparatus includes a treatment chamber (2) having a cathode (9) and an anode (3) opposing each other. Electrical energy is applied to microorganisms contained in the water. The anode and/or the water in the vicinity of the anode is vibrated and debris inside and outside the chamber is removed (17).

Abstract: Applying electrical energy to a microorganism through a liquid, gas or solid having electrical energy causes an increase in an electric charge in excess of the limit of intracellular and extracellular electrostatic capacity possessed by the microorganism, which results in an irreversible change in the microorganism cells and/or explosively destroys the border membrane of the microorganism cells.

Abstract: An acrylic fiber precursor for high performance carbon fibers free of defects which comprises an acrylonitrile polymer containing at least 90% by weight of acrylonitrile and has a surface roughness of 2.0 to 3.0 with dense inner structure. from a solution comprising 24 to 27.5% of the acrylonitrile polymer is dry-jet wet spun into a coagulation bath consisting essentially of dimethylformamide or dimethylacetamide and having a bath temperature of 5.degree. to 25.degree. C.Carbon fibers obtained by carbonizing these precursor acrylic fibers have no fusion bonding or agglutination of filaments and exhibit high performance.

Abstract: A mechanical hand amusement device consisting of a movable grip member joined by a rod, which extends through a tubular arm, to a hand member having a fixed thumb and four finger members which bend inward when the grip member is squeezed. Each finger member includes three hollow segments which are joined by flexible hinges at the tops, and have a flexible strap which is anchored within the fingertip segment running along the bottoms. The strap extending through each of the finger members is coupled to the rod so that a portion of the strap is retracted into the hand member when the grip member is squeezed. The resulting forces move the finger members inward in a grasping motion. A spring within the hand member returns the elements to their at-rest positions when the grip member is released.

Abstract: A mechanical hand amusement device consisting of a movable grip member joined by a rod, which extends through a tubular arm, to a hand member having a fixed thumb and four finger members which bend inward when the grip member is squeezed. Each finger member includes three hollow segments which are joined by flexible hinges at the tops, and have a flexible strap which is anchored within the fingertip segment running along the bottoms. The strap extending through each of the finger members is coupled to the rod so that a portion of the strap is retracted into the hand member when the grip member is squeezed. The resulting forces move the finger members inward in a grasping motion. A spring within the hand member returns the elements to their at-rest positions when the grip member is released.

Abstract: There are disclosed porous polypropylene hollow filaments which have a surrounding wall portion of less than 60 .mu., preferably 40 .mu. in thickness which contains many fine holes communicating with each other, distribution curve of radius of said fine holes having at least one maximum points within the range of 200-1200 A. The method for producing said porous polypropylene hollow filaments is also disclosed.