Abstract: A virtual-image forming device includes a device body having an opening; a real-image forming unit disposed within the device body to output light; a mirror to reflect the light output from the real-image forming unit; and an optical element. The optical element has positive power to refract the light reflected by the mirror and let the light exit through the opening to form of the light on a transmission and reflection member.

Abstract: An image-forming lens includes, from an object side to an image side in order: a first lens group; an aperture; and a second lens group with a positive refractive power, the first lens group including, from the object side in order: a first F lens group with a negative refractive power; and a first R lens group with a positive refractive power, the first F lens group including, from the object side in order: a first negative lens; and a second negative lens, and the first R lens group including: any one of a positive lens and a cemented lens with a positive refractive power as a whole, wherein a distance from a surface on a most object side of the first lens group to an image plane in a state of focusing on an object at infinity: L, and a maximum image height: Y? satisfy Conditional expression 1: 2.8<L/Y?<4.3.

Abstract: According to an embodiment, a projection optical system for an image projection device, that includes a plurality of lenses. The projection optical system satisfies conditional expression (1): where fw is a focal length of a lens having the weakest refractive power in the lenses and f is a focal length of the whole projection optical system. 0.01 ? ? f f w ? < 0.

Abstract: An optical system includes an optical element configured to emit light emitted from a light source; and an optical modulation element configured to receive the light emitted from the optical element and emit first light rays in a first direction and second light rays in a second direction different from the first direction.

Abstract: A composite bump includes a plurality of first bumps that is metal-bonded to an electrode pad of a semiconductor chip, and a second bump that is metal-bonded to the plurality of first bumps. A method for forming a composite bump, includes forming a plurality of first bumps to be metal-bonded to an electrode pad of a semiconductor chip, and forming a second bump to be metal-bonded to the plurality of first bumps.

Abstract: An optical module includes: a substrate including a through hole, a first chip including a first heating member and disposed in the through hole, a second chip including a second heating member and bonded to a first upper surface of the substrate and a second upper surface of the first chip via bumps, and a first heat sink adhered to a lower surface of the substrate with a first adhesive and adhered to a lower surface of the first chip with a second adhesive, wherein the substrate includes a slit which is provided on a side of a first portion, to which the second chip is bonded, of the substrate with respect to the through hole, and communicates with the through hole.

Abstract: A polyolefin microporous membrane in which defects including scratches and pinholes can be stably detected, even when the membrane has a reduced thickness, has a light transmittance at a wavelength of 660 nm of 40% or less, and satisfies at least one of the following properties (1) and (2), wherein (1) the basis weight is 3.0 g/m2 or less, and (2) the membrane thickness is 4 ?m or less.

Abstract: The present invention provides a conductive material in which, even when the conductive material is left for a certain period of time, solder can efficiently placed on an electrode, and, in addition, wettability of the solder can be improved. The conductive material according to the present invention contains a thermosetting compound and a plurality of solder particles, and the concentration of free tin ions in the conductive material is 100 ppm or less.

Abstract: A projection zoom lens constituting a projection optical system of a projector, which projects an image displayed on a surface of an image display element on a projected surface, so as to magnify and display the image includes, in order from the projected surface side to the image display element side, a first lens group having a negative refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, and a fifth lens group, wherein a refractive power of the fifth lens group is weaker than the refractive power of the first lens group, the refractive power of the second lens group, the refractive power of the third lens group, and the refractive power of the fourth lens group.

Abstract: Disclosed is a projection zoom lens used in an image display device configured to project an image onto a target projection surface and display a magnified image of the image, in which the projection zoom lens has a five-lens-group configuration in which first to fifth lens groups G1 to G5 are arranged from the magnification side toward the reduction side, and each of the constituent lens groups or lenses included in the lens groups has a combination of negative and positive refractive powers, and in the lens configuration, focal lengths of the constituent lens groups, relative travel distances, lens distances to the image display element, and constituent lens shapes are properly selected.

Abstract: An optical module includes a substrate, a silicon photonics chip disposed in an opening of the substrate, a control chip disposed across the substrate and the silicon photonics chip, a plurality of laser diodes disposed over the silicon photonics chip, and a metallic bar in contact with each of terminals of the plurality of laser diodes and electrically coupling each of the terminals with the silicon photonics chip or the substrate.

Abstract: A board module includes a first board having an inner wall that has a protrusion and defines a through hole. The board module includes a second board provided in the through hole and joined to the protrusion by using a resin. The board module includes a third board joined above and across the first board and the second board.

Abstract: An optical module includes: a substrate including a through hole, a first chip including a first heating member and disposed in the through hole, a second chip including a second heating member and bonded to a first upper surface of the substrate and a second upper surface of the first chip via bumps, and a first heat sink adhered to a lower surface of the substrate with a first adhesive and adhered to a lower surface of the first chip with a second adhesive, wherein the substrate includes a slit which is provided on a side of a first portion, to which the second chip is bonded, of the substrate with respect to the through hole, and communicates with the through hole.

Abstract: A light guide includes a light-guide member including an incidence portion through which image light emitted from an image display element enters the light-guide member; an exit portion through which the image light exits the light-guide member to an outside of the light-guide member; a retroreflection portion to reverse a direction of travel of the image light guided through the light-guide member; and an extraction portion to guide the image light reversed by the retroreflection portion to the exit portion. The retroreflection portion has a plurality of surfaces.

Abstract: An image display device includes a high-performance projection zoom lens with a very wide field angle and an image display device including a projection zoom lens of a five-lens-group type, which achieves high performance across the entire zoom area. The image display device is configured to project an image onto a target projection surface and display a magnified image of the image, which uses a projection zoom lens having a five-lens-group configuration in which first to fifth lens groups G1 to G5 are arranged from the magnification side toward the reduction side, and each of the constituent lens groups or lenses included in the lens groups has a combination of negative and positive refractive powers, and in the lens configuration, focal lengths of the constituent lens groups, relative travel distances, lens distances to the image display element, and constituent lens shapes are properly selected.

Abstract: A light guide for a virtual image device to guide and emit image light output from an image display element to display a virtual image. The light guide includes a light-guide member and an optical member. The light-guide member includes an incidence portion to receive the image light and an exit portion to emit the image light to an outside, and a reflective portion inclined relative to the incidence portion to guide the image light received by the incidence portion into the light guide. The light-guide member also includes an extraction portion including first planes each inclined relative to the exit portion and second planes each parallel with the exit portion, to guide the image light from each first plane to the exit portion and extract the image light. The optical member includes a parallel plane and an inclined portion.

Abstract: An optical module includes a substrate, a silicon photonics chip disposed in an opening of the substrate, a control chip disposed across the substrate and the silicon photonics chip, a plurality of laser diodes disposed over the silicon photonics chip, and a metallic bar in contact with each of terminals of the plurality of laser diodes and electrically coupling each of the terminals with the silicon photonics chip or the substrate.

Abstract: A composite bump includes a plurality of first bumps that is metal-bonded to an electrode pad of a semiconductor chip, and a second bump that is metal-bonded to the plurality of first bumps. A method for forming a composite bump, includes forming a plurality of first bumps to be metal-bonded to an electrode pad of a semiconductor chip, and forming a second bump to be metal-bonded to the plurality of first bumps.

Abstract: A virtual-image forming device includes a device body having an opening; a real-image forming unit disposed within the device body to output light; a mirror to reflect the light output from the real-image forming unit; and an optical element. The optical element has positive power to refract the light reflected by the mirror and let the light exit through the opening to form of the light on a transmission and reflection member.

Abstract: A projection optical system is for an image projection device. The projection optical system includes a whole lens system of seven to nine lenses and an aperture stop. The seven to nine lenses are all single lenses. One negative lens and one or two positive lenses are located on a magnifying side with respect to the aperture stop. Two negative lenses and three or four positive lenses are located on a reducing side with respect to the aperture stop. A lens adjacent to the magnifying side of the aperture stop and a lens adjacent to the reducing side of the aperture stop are both a negative lens.