Abstract: A spread illuminating apparatus includes: at least one light source; a light conductive plate which has the at least one light source disposed at one end surface thereof, and which allows light emitted from the at least one light source and introduced therein to exit out therefrom through both major surfaces thereof toward first and second liquid crystal display elements disposed respectively over the both major surfaces of the light conductive plate, wherein the second liquid crystal display element has a smaller display screen size than the first liquid crystal display element; and a reflecting means which is disposed at the other major surface of the light conductive plate so as to cover at least areas not covered by the second liquid crystal display element, and which reflects light toward the first liquid crystal display element.

Abstract: A spread illuminating apparatus includes a light conductive plate provided with a light entry face at its corner, having a spot-like light source disposed close to or in contact with the light entry face, and having a light reflection pattern formed on its major surface. The light reflection pattern comprises a plurality of arced grooves and is configured such that the grooves have their depths increasing with an increase in the distance from the light source, and that each of the grooves has its depth increasing with an increase in the light emission angle made by a line of a light emission direction with respect to a diagonal line from the light source. Thus, the light reflection pattern is adapted to reflect more light at an area farther from the light source and the diagonal line as well, thereby further improving uniformity in brightness all over the light conductive plate.

Abstract: A magnetic head exhibits a good traceability without damaging itself or a magnetic disk. The magnetic head includes a slider, and the slider includes a plurality of magnetic cores and an outrigger having a plurality of substantially rectangular slots. The magnetic cores have respective operating gaps for a standard recording density and a high recording density and are inserted into the respective substantially rectangular slots. One magnetic core for a high recording density having a spacer superposed thereon is inserted in one of the slots in such a manner as to touch a wall of the slot. The slider includes a rail surface which has a groove passing longitudinally through the spacer substantially at the center of its thickness and reaching both lengthwise ends of the slider, and the rail surface slides against a magnetic recording medium.

Abstract: A plurality of minute lenticular elements made of a light-transmissible material and each having a substantially plano-convex cross section are formed on a major surface of a light conductive plate opposite to another major surface provided with a light reflection pattern, and are arranged radially with respect to a spot-like light source with their respective longitudinal directions oriented perpendicular to grooves of the light reflection pattern. Light rays guided in the lenticular element from its bottom surfaces are spread in a circumferential direction of its outer curved surfaces. A view field angle can be increased by the lenticular element in a direction tangential to the grooves improving view field angle distribution.

Abstract: A method of manufacturing magnetic heads is provided in which a slider and a back yoke are joined to form a magnetic head main body. The main body is then fixedly bonded to a holding member that supports the magnetic head as a single unit. A plurality of such magnetic heads are placed circumferentially on a soft adhesive sheet attached to a cylindrical base block. Touch lapping is then performed to a slider surface of the magnetic heads with a slurry on a surface table. Processing faces of the heads can be positioned flush with the surface table due to an elasticity of the soft adhesive sheet, thereby equally minimizing lapping amounts.

Abstract: An information reading and recording apparatus in which recording media having respective recording densities different front each other, such as DVD, CD, CD-R/RW and the like, can be compatibly read and recorded only with a low-cost laser diode for low recording density. A laser beam from the laser diode is passed through a collimator lens via a half mirror, and there is provided a reflecting mirror for introducing the laser beam to one of two objective lenses, from which the laser beam is emitted towards the disk. One of the objective lenses is a lens having a high numerical aperture and the other one is a lens having a low numerical aperture. A super-resolution cut-off filter is disposed immediately before the objective lens having a high numerical aperture so that the objective lens and the super-resolution cut-off filter are placed in the optical path on reading DVD. On reading CD, the other lens is placed in the optical path.

Abstract: The present invention provides a spread illuminating apparatus for improving the machinability and durability of a molding die for a transparent substrate and obtaining an excellent light reflection. In a light reflection pattern comprising grooves and substantially flat portions adjacent to the grooves and formed on an upper surface of the transparent substrate in parallel to the optical axis of a bar-like light conductive member located close to an end surface of the transparent substrate, the grooves are each formed substantially trapezoidal in section with their bottom surface defining a shorter side of trapezoid.

Abstract: A plurality of workpieces W (single units each formed by bonding together a magnetic head main body and either a mount block or a gimbals) are circumferentially placed on a soft adhesive sheet (for example, a low elasticity rubber formed of urethane and having a thickness of approx. 5 mm) attached to a base block in such a manner that a slider surface is positioned at a side opposite to the sheet, then the slider surfaces are lapped with a slurry on a surface table. Processing faces of the workpieces W can be positioned flush with the surface table due to an elasticity of the soft adhesive sheet, thereby equally minimizing lapping amounts.

Abstract: A spread illuminating apparatus provides a uniform illuminance, an accurate illumination, an improved visibility, and an expanded screen size. Light sources (5a, 5b) comprising bar-like light conductive members (3a, 3b) and spot-like light sources (4a, 4b), respectively, are disposed close to end surfaces (8a, 8b) of a transparent substrate (2). A light reflection pattern (29) is formed on a surface of the transparent substrate (2) along the length of the light conductive members (3a, 3b). The light reflection pattern (29) comprises grooves (27) and flat portions (28) adjacent to the grooves. The grooves (27) are shaped trapezoidal in section, and the depth thereof increases in proportion to the increase in distance from the light sources (5a, 5b) and measures maximum at the center of the transparent substrate (2).

Abstract: A magnetic head that is excellently adapted to a magnetic core reduced in thickness. When a magnetic core which is reduced in thickness for adaptation to a high recording density is inserted in an opening of a size conventionally formed in a magnetic head of a standard recording density type, a spacer made of a material equivalent or identical to that of a slider is inserted between the magnetic core and the inner wall of the opening. The magnetic core is positioned by means of projections formed on the inner wall of the opening and the spacer. Then, glass as a sealing material is poured into gaps formed in the opening by the magnetic core, the inner wall of the opening and the spacer. The inserted spacer reduces a space volume for the glass to be poured. Further, since the spacer is made of the material equivalent or identical to that of the slider, a partial abrasion at a sliding surface of the slider sliding on a recording medium can be eliminated.

Abstract: A magnetic head which can improve workability in coil formation, prevent wiring errors and is compatibly applicable to recording media having respective recording densities different from each other. Twelve cut-outs (11) are formed on four walls (10) at respective edges of a back yoke (5) and lead wires (15a, 15b) of a read/write coil (15) and lead wires (16a, 16b) of a read/write coil (16) are let separately through the respective cut-outs (11), whereby the lead wires (15a, 15b and 16a, 16b) are not mistaken for each other in wiring. Since first and second magnetic cores (2 and 3) and the read/write coils (15 and 16) corresponding thereto are provided, the magnetic head is capable of reading and writing on two recording media having respective recording densities different from each other, thereby providing compatibility for magnetic recording.

Abstract: A spread illuminating apparatus combined with a liquid crystal display via a frame has a reduced thickness as a whole, thereby realizing a natural liquid crystal display image. A light conductive plate has its peripheral portion fitted in a groove of the frame, and a lamp disposed on a side surface of the light conductive plate is housed in the frame. A top side portion of the liquid crystal display is fitted into a cut-away portion of the frame by a predetermined dimension, and a space between a bottom surface of the light conductive plate and a top surface of the liquid crystal display is reduced, whereby the thickness of the entire apparatus is reduced by a dimension of the liquid crystal display fitted into the frame compared with that of the conventional configuration in which the frame is superimposed on the top surface of the liquid crystal display.

Abstract: There is provided a spread illuminating apparatus in which a bar-like light source radiates light more uniformly. Light scattering portions are formed to be inclined in a longitudinal direction of a light conductive member such that irradiation ranges of adjacent light scattering portions overlap partially with each other in the longitudinal direction of the light conductive member. Light ranges (La1 La2, La3, La4 and La5) in a longitudinal direction of the light conductive member per beam of light reflected at the light scattering portions and entering a transparent substrate are expanded so as to overlap partially with each other. Accordingly, the light conductive member includes no part that the light reflected at an optical path conversion means of the light conductive member does not cover in the longitudinal direction of the light conductive member. Thus, the light conductive member constitutes a light source that spreads uninterrupted linear light even on a microscopic level.

Abstract: A spread illuminating apparatus comprises: a light conductive plate made of a light transmissible material; a bar-like lamp disposed along and close to an end face of the light conductive plate; a light reflection pattern having a stair-like configuration in section, and formed on a major face of the light conductive plate; and a light dispersive-reflection pattern comprising a plurality of, for example, convex surfaces continuous with each other, and formed on a major face of the light conductive plate opposite to the major face provided with the light reflection pattern.

Abstract: There is provided a spread illuminating apparatus to suppress the appearance of moiré fringes. A light reflection pattern of a transparent substrate is composed of grooves of substantially triangular in section and flat portions adjacent thereto. The light reflection pattern is formed substantially parallel to the optical axis of a bar-like light source and the depth of the grooves increases gradually in proportion to the increase in distance from the light source. The interval of the adjacent grooves (the groove interval) is set to vary irregularly. Thereby, the relation between the interval of grooves and the interval of mosaic pattern of liquid crystal cells is not definite, and the appearance of moiré pattern can be suppressed.

Abstract: A spread illuminating apparatus includes a light conductive plate provided with a light entry face at its corner, having a spot-like light source disposed close to or in contact with the light entry face, and having a light reflection pattern formed on its major surface. The light reflection pattern comprises a plurality of arced grooves and is configured such that the grooves have their depths increasing with an increase in the distance from the light source, and that each of the grooves has its depth increasing with an increase in the light emission angle made by a line of a light emission direction with respect to a diagonal line from the light source. Thus, the light reflection pattern is adapted to reflect more light at an area farther from the light source and the diagonal line as well, thereby further improving uniformity in brightness all over the light conductive plate.

Abstract: There is provided a spread illuminating apparatus realizing both uniform light emission and high brightness. Two bar-like light conductive members made of a transparent material and each having a spot-like light source disposed on a large end thereof are disposed so as to overlap with each other in the thickness direction of a transparent substrate, thereby constituting a pair of bar-like light sources. Light emitted from the spot-like light source and entering one light conductive member of the two is directly guided into the transparent substrate without passing through the other light conductive member. Thus, light rays emitted from the two light conductive members do not interfere with each other so as to prevent generation of interference fringes, resulting in that uniform light emission and high brightness in the spread illuminating apparatus can be realized.

Abstract: There is provided a spread illuminating apparatus aiming to minimize the coverage of a liquid crystal screen while securely integrating a light conductive member with a transparent substrate. The light conductive member is wedge-shaped in which the width thereof is in inverse proportion to the increase in distance from a spot-like light source opposing face, and the transparent substrate is trapezoid-shaped in which a side aligned to the spot-like light source opposing face is shorter. A frame and transparent substrate overlapping part becomes larger from one side part to the other side part of the transparent substrate. Since the frame and transparent substrate overlapping part are large enough regardless of the small width of the frame than that of the prior art, the region of a liquid crystal screen can be increased accordingly.

Abstract: A laser beam emitted from a laser diode and having a wavelength of 780 nm is S-polarized. A polarization plane rotating means (&lgr;/4 phase plate) is disposed between a super-resolution cut-off filter comprising a polarizing filter film and an objective lens. When reading on DVD, the objective lens, the polarization plane rotating means and the super-resolution cut-off filter in combination are set to the optical path. The S-polarized laser beam is focused to a micro spot diameter by super-resolution effects by the super-resolution cut-off filter together with the objective lens. Also, the S-polarized laser beam reflected at a disk and traveling backward along the incoming optical path is converted into a P-polarized laser beam while passing backward through the polarization plane rotating means. The P-polarized laser beam passes through the super-resolution cut-off filter without loss is received by a photo-detector.

Abstract: An optical pickup apparatus for reading and recording information on recording media includes a semiconductor laser, a collimating lens, a half mirror, a reflecting mirror, and an objective lens. Further included therein are a super-resolution cutoff filter and an aperture control filter, one of which is appropriately selected and set right before the objective lens by a filter switching-over device. When reading the DVD, the super-resolution cutoff filter is set at the optical path, whereas when reading the CD, the aperture control filter is set thereat. The filter switching device is arranged separately from an actuator driving system having the objective lens integrally structured therewith.