Abstract: A lighting optical unit having an optical system for irradiating light from a light-source lamp on a predetermined object in a uniform and/or convergent manner includes a reflector for reflecting light from the light-source lamp to provide converged light and an optical assembly for collimating this converged light to provide a bundle of approximately parallel rays, wherein the bundle of approximately parallel rays is made to enter the optical systeml. Thus, in a liquid-crystal projector using a transmission type liquid-crystal panel with micro-lens, while a demand for increasing a quantity of light incident on an effective area of pixel of a liquid-crystal panel is being satisfied, the lighting optical unit can be made compact in size.

Abstract: An apparatus for transmitting or reflecting incident light. The apparatus includes a pair of diffraction grid substrates; a substantially grid-shaped diffraction grid formed of metal, wherein the diffraction grid is disposed between the substrates; and a pair of adhesive layers, each adhesive layer coupled to each substrate. The apparatus also includes a pair of block members, wherein each block member is coupled to each adhesive layer. The block member is configured with a plurality of substantially equally-shaped flat plate members alternately layered with adhesive layers for optically coupling the block member with substantially reduced optical distortion than when configured with a single transparent component. The block member includes a surface to output the light transmitted or reflected from the diffraction grid and passing through the flat plate members.

Abstract: Provided are an illumination optical system having superior color rendering properties while ensuring sufficient illuminance, an image display apparatus comprising the illumination optical system and a spatial modulation device illuminated by the illumination optical system, and a method of illuminating the spatial modulation device. A first light source (11), a second light source (21) having a different emission spectrum from an emission spectrum of the first light source (11), and a replacement optical system replacing light in a specific waveband in a luminous flux (L1) from the first light source (11) with a luminous flux (L2) from the second light source (21) are comprised, and the light in the specific waveband with weak light intensity in the luminous flux (L1) from the first light source (11) is replaced with the luminous flux (L2) with sufficient intensity from the second light source (21).

Abstract: An apparatus for transmitting or reflecting incident light. The apparatus includes a pair of diffraction grid substrates; a substantially grid-shaped diffraction grid formed of metal, wherein the diffraction grid is disposed between the substrates; and a pair of adhesive layers, each adhesive layer coupled to each substrate. The apparatus also includes a pair of block members, wherein each block member is coupled to each adhesive layer. The block member is configured with a plurality of substantially equally-shaped flat plate members alternately layered with adhesive layers for optically coupling the block member with substantially reduced optical distortion than when configured with a single transparent component. The block member includes a surface to output the light transmitted or reflected from the diffraction grid and passing through the flat plate members.

Abstract: A prism optimally separating and synthesizing a light beam of a wide angle of incidence. A diffraction prism 15 of the present invention is so constructed that a diffraction grid 21 is sandwiched between a pair of diffraction grid substrates 22, a pair of prism substrates 24 are bonded to the surfaces of the prism substrates 22 facing the diffraction grid 21 with interposition of adhesive layers 23, and a diffraction grid medium 25 having a refractive index substantially equal to that of the prism substrates 24 is charged in a gap defined by the diffraction grid 21 and the prism substrates 24, with the respective component members being optically combined together. An incident light is led to the diffraction grid 21 and separated on transmission or reflection by the operation of diffraction by the diffraction grid 21.

Abstract: Provided are an illumination optical system having superior color rendering properties while ensuring sufficient illuminance, an image display apparatus comprising the illumination optical system and a spatial modulation device illuminated by the illumination optical system, and a method of illuminating the spatial modulation device. A first light source (11), a second light source (21) having a different emission spectrum from an emission spectrum of the first light source (11), and a replacement optical system replacing light in a specific waveband in a luminous flux (L1) from the first light source (11) with a luminous flux (L2) from the second light source (21) are comprised, and the light in the specific waveband with weak light intensity in the luminous flux (L1) from the first light source (11) is replaced with the luminous flux (L2) with sufficient intensity from the second light source (21).

Abstract: A lighting optical unit having an optical system 13 to 16 for irradiating light from a light-source lamp 11 on a predetermined object 22 in a uniform and/or convergent manner includes a reflector 1 for reflecting light from the light-source lamp 11 to provide converged light and an optical assembly 2 for collimating this converged light to provide a bundle of approximately parallel rays, wherein the bundle of approximately parallel rays is made to enter the optical system 13 to 16. Thus, in a liquid-crystal projector using a transmission type liquid-crystal panel with micro-lens, while a demand for increasing a quantity of light incident on an effective area of pixel of a liquid-crystal panel is being satisfied, the lighting optical unit can be made compact in size.

Abstract: A projection apparatus is disclosed which uses a light modulation element of the reflection type and can demultiplex and multiplex light appropriately. The projection apparatus includes four PBSs including an incoming PBS, a RB-PBS, a G-PBS and an outgoing PBS to demultiplex illumination light emitted from a lamp into light components in wavelength bands of blue, red and green. The illumination light in the wavelength band of green is introduced to a position at which the highest contrast is obtained, and a third liquid crystal panel is disposed at the position. The illumination light in the wavelength band of red is introduced to another position at which the second highest contrast is obtained, and a second liquid crystal panel is disposed at the position. The illumination light in the wavelength band of blue is introduced to the remaining position, and a first liquid crystal panel is disposed at the position.

Abstract: A prism optimally separating and synthesizing a light beam of a wide angle of incidence. A diffraction prism 15 of the present invention is so constructed that a diffraction grid 21 is sandwiched between a pair of diffraction grid substrates 22, a pair of prism substrates 24 are bonded to the surfaces of the prism substrates 22 facing the diffraction grid 21 with interposition of adhesive layers 23, and a diffraction grid medium 25 having a refractive index substantially equal to that of the prism substrates 24 is charged in a gap defined by the diffraction grid 21 and the prism substrates 24, with the respective component members being optically combined together. An incident light is led to the diffraction grid 21 and separated on transmission or reflection by the operation of diffraction by the diffraction grid 21.

Abstract: A projection apparatus is disclosed which uses a light modulation element of the reflection type and can demultiplex and multiplex light appropriately. The projection apparatus includes four PBSs including an incoming PBS, a RB-PBS, a G-PBS and an outgoing PBS to demultiplex illumination light emitted from a lamp into light components in wavelength bands of blue, red and green. The illumination light in the wavelength band of green is introduced to a position at which the highest contrast is obtained, and a third liquid crystal panel is disposed at the position. The illumination light in the wavelength band of red is introduced to another position at which the second highest contrast is obtained, and a second liquid crystal panel is disposed at the position. The illumination light in the wavelength band of blue is introduced to the remaining position, and a first liquid crystal panel is disposed at the position.

Abstract: A semiconductor device can be prevented from mal-functioning by interrupting reflected beam. Polarizing plates (1), (3) are disposed at beam entrance and exit sides, respectively of a transmission liquid-crystal display device (2) as polarizers. Beam from the polarizing plate (3) has the change of light and shade presented in accordance with a video signal. An optical isolator using a quarter-wave plate (4) is disposed at the beam exit side of the polarizing plate (3). A glass panel (5) such as an optical filter is disposed at the beam exit side of the quarter-wave plate (4), whereby beam from the polarizing plate (3) is converted into linearly-polarized beam having an arbitrary plane of polarization. When this linearly-polarized beam is introduced into the optical isolator using the quarter-wave plate (4), inputted linearly-polarized beam is converted into circularly-polarized beam by action of the quarter-wave plate (4). The thus converted circularly-polarized beam is irradiated on the glass panel (5).

Abstract: A magnetic recording/reproducing head assembly comprising a first magnetic path forming member on which a coil is mounted, a second magnetic path forming member which forms a magnetic path in cooperation with the first magnetic path forming member, and a film laminate formed at a front gap portion between the first magnetic path forming member and the second magnetic path forming member. The film laminate includes a magnetic detecting element for detecting a change in a magnetic field and a soft magnetic film or films. This magnetic head assembly is prepared by forming the film laminate on a head base of the head assembly, bonding a core member to the head base with the film laminate formed thereon, and mounting a coil on the core member.

Abstract: A magnetoresistive head including a magnetoresistive element in which the magnetoresistive head has a specifically determined gap length and/or the magnetoresistive element has a specifically determined magnetostriction constant to thereby define a reproduction output vs. operation current characteristic curve of the head. The above-mentioned gap length and/or magnetostriction constant is determined such that a saturation operation current for which a reproduction output of the head is maximum is higher than an operation current with which the head is operative.

Abstract: The present invention relates to the structure of a magneto-resistive head for reducing the spike noises generated in the head and for increasing the signal to noise ratio when the information is reproduced. In order to achieve the object, an electric conductor layer is disposed at both sides or one side of a magneto-resistive element, and the conductor layer is isolated from the element and connected to a DC potential.

Abstract: A magnetroresistive element formed by laminating a plurality of metallic magnetoresistance effect films having magnetostriction of different signs on a substrate. The magnetoresistive element can be formed to exhibit zero magnetostriction or to exhibit magnetostriction of any desired value. Further, the magnetoresistive element exhibits magnetostriction that changes little with the change in the film composition. The metallic magnetoresistance effect films preferably have positive and negative magnetostriction with an absolute value not greater than 15.times.10.sup.-6.