Abstract: A lens unit includes a first lens (2) and a second lens (3) housed in a holder (1) which may improve aberration. The first lens (2) is cylindrical having a top that functions as a lens (2a), and the second lens (3) is pressed into the cylindrical portion (2b) of the first lens (2) having a top in such a manner that the inner periphery of the cylindrical portion (2b) of the first lens (2) is pressed by the outer periphery of the second lens (3).

Abstract: A viscoelastic polisher to be used for polishing. The viscoelastic polisher includes a viscoelastic layer provided on a major surface of a base disk and having a hole of a predetermined radius formed in a center portion thereof, and the base disk has a plurality of grooves equiangularly provided in the major surface thereof as extending radially outward from a center portion thereof. This arrangement ensures stable supply of an abrasive liquid, and obviates a need for formation of grooves in the viscoelastic layer.

Abstract: The drop impact measuring system has i) a plurality of bimorph-type acceleration sensor containing a plurality of free vibrating sections each of which has individual draw-out electrodes; ii) a switch section for selecting output from the bimorph-type acceleration sensors; iii) an amplifying circuit for amplifying a signal applied via the switch section from the acceleration sensors; and iv) a logic circuit for logically evaluating the output from the amplifying circuit and controlling the switch section according to the result acquired from the logical evaluation.

Abstract: A lens unit includes a lens holder having an opening and an inner wall, the lens having an optical axis passing through the opening, a first lens having an outer circumference, and arranged in the lens holder along the optical axis, a second lens having an outer circumference, and arranged in the lens holder along the optical axis, and three strut portions provided on the inner wall of the lens holder. The strut portions position the first lens and the second lens. The strut portions have surfaces facing the optical axis, respectively, the surfaces of the strut portions slanting with respect to the optical axis and contacting the outer circumference of the first lens and the outer circumference of the second lens. This lens unit has the lenses positioned accurately.

Abstract: The drop impact measuring system has i) a plurality of bimorph-type acceleration sensor containing a plurality of free vibrating sections each of which has individual draw-out electrodes; ii) a switch section for selecting output from the bimorph-type acceleration sensors; iii) an amplifying circuit for amplifying a signal applied via the switch section from the acceleration sensors; and iv) a logic circuit for logically evaluating the output from the amplifying circuit and controlling the switch section according to the result acquired from the logical evaluation.

Abstract: A substrate on which cavities having floors and steps is provided. End faces of a light-emitting device, an optical component, and an optical transmission line are abutted on one of the cavity for positioning, and end faces of a light-receiving device, an optical component, and an optical transmission line are also abutted on the other cavity for positioning. Integrated alignment of optical axes facilitates alignment of optical axes, and thus eliminates the need of a CAN package. Accordingly, the size and height of an optical communications module can be reduced.

Abstract: A viscoelastic polisher to be used for polishing. The viscoelastic polisher includes a viscoelastic layer provided on a major surface of a base disk and having a hole of a predetermined radius formed in a center portion thereof, and the base disk has a plurality of grooves equiangularly provided in the major surface thereof as extending radially outward from a center portion thereof. This arrangement ensures stable supply of an abrasive liquid, and obviates a need for formation of grooves in the viscoelastic layer.

Abstract: Precise V-grooves allowing an optical fiber to project are formed in respective main surfaces of an upper plane substrate and a lower plane substrate. The optical fiber is mounted on one plane substrate, and a multi-layer film filter 2 is inserted into a filter insertion groove 1 crossing the precise V-groove in the main surface of the other plane substrate. Then, using the projecting optical fiber and the other precise V-groove as a guide rail, two plane substrates grapple the multi-layer film filter to fix and mount the filter. In an optical filter module obtained in this manner, a process of adjusting an optical axis between input/output optical fibers is eliminated, and displacement of the inserted optical filter is reduced.

Abstract: An optical filter module having a multilayered filter inserted in the paths of optical waveguides thereof. In the optical filter module, precise V-shaped grooves are formed on the principle plane of a plane substrate so that optical fibers protrude therefrom. The optical fibers are mounted on the plane substrate. After the multilayered filter is inserted in a filter insertion groove that is formed so as to intersect the V-shaped grooves on the plane substrate, the filter is sandwiched and clamped by two sheets of covers provided on the plane substrate. Provided is a method of precisely mounting the filter that improves the optical axis adjustment between input and output optical fibers and reduces misregistration of the filter to be inserted.

Abstract: An optical component is provided for optical communication and has a smaller size and a shorter height. The optical component involves a concave package provided by layering ceramic substrates, a groove section formed at a bottom face of this package, an optical semiconductor element provided in this groove section, a cover provided to cover an opening section of the package and a lens formed at the cover.

Abstract: An optical filter module of the present invention has a flat substrate, an optical path formed on the flat substrate; a filter insertion groove provided, crossing the optical path, on the flat substrate; a multilayer filter inserted, dividing the optical path, into the filter insertion groove; and a pair of covers disposed on the flat substrate so as to sandwich the multilayer filter. The present invention enables the omission of the process of adjustment of the optical axis, thus achieving high operability. At the same time, the present invention ensures fixing and mounting of the multilayer filter even if the multilayer filter is warped.

Abstract: The drop impact measuring system has i) a plurality of bimorph-type acceleration sensor containing a plurality of free vibrating sections each of which has individual draw-out electrodes; ii) a switch section for selecting output from the bimorph-type acceleration sensors; iii) an amplifying circuit for amplifying a signal applied via the switch section from the acceleration sensors; and iv) a logic circuit for logically evaluating the output from the amplifying circuit and controlling the switch section according to the result acquired from the logical evaluation.

Abstract: A piezoelectric vibrator which uses lithium tantalate as a piezoelectric material and of which main vibration is thickness shear vibration. The thickness direction of the vibrator forms angle of 0°±5° to the X-axis of a single crystal. The longitudinal direction of vibrator lies, with the X-axis used as a rotation axis, in direction n +57°±2° clockwise from the Y-axis of the single crystal. A ratio L/H of the length L of the vibrator to the thickness H is not less than 15. A ratio Le/H of the length Le of the exciting electrode to the thickness H of the vibrator element portion is 3–6. Accordingly, a vibrator having improved temperature characteristics and a large Q is realized.

Abstract: The drop impact measuring system has i) a plurality of bimorph-type acceleration sensor containing a plurality of free vibrating sections each of which has individual draw-out electrodes; ii) a switch section for selecting output from the bimorph-type acceleration sensors; iii) an amplifying circuit for amplifying a signal applied via the switch section from the acceleration sensors; and iv) a logic circuit for logically evaluating the output from the amplifying circuit and controlling the switch section according to the result acquired from the logical evaluation.

Abstract: A substrate on which cavities having floors and steps is provided. End faces of a light-emitting device, an optical component, and an optical transmission line are abutted on one of the cavity for positioning, and end faces of a light-receiving device, an optical component, and an optical transmission line are also abutted on the other cavity for positioning. Integrated alignment of optical axes facilitates alignment of optical axes, and thus eliminates the need of a CAN package. Accordingly, the size and height of an optical communications module can be reduced.

Abstract: The object of the present invention is to provide a lens unit with first lens (2) and second lens (3) housed in holder (1) which may improve the aberration. It comprises cylindrical holder (1), first lens (2) and second lens (3) housed in holder (1). First lens (2) is cylindrical having a top that functions as lens (2a), and second lens (3) is pressed into cylindrical portion (2b) of first lens (2) having a top in such manner that the inner periphery of cylindrical portion (2b) of first lens (2) is pressed by the outer periphery of second lens (3).

Abstract: A lens unit includes a lens holder having an opening and an inner wall, the lens having an optical axis passing through the opening, a first lens having a outer circumference, and arranged in the lens holder along the optical axis, a second lens having a outer circumference, and arranged in the lens holder along the optical axis, and three strut portions provided on the inner wall of the lens holder. The strut portions position the first lens and the second lens. The strut portions have surfaces facing the optical axis, respectively, the surfaces of the strut portions slanting with respect to the optical axis and contacting the outer circumferences of the first lens and the outer circumferences of the second lens. This lens unit have the lenses positioned accurately.

Abstract: An electronic apparatus is provided that comprises a shock detector for detecting a shock received by an electronic apparatus such as a portable telephone, a controller for comparing the value of the shock as detected by the shock detector with a reference value, and a memory element for storing an identifying signal generated when the value of a shock has exceeded the reference value and the value of shock. This enabling easy determination as to whether or not a breakdown has been caused by shock.

Abstract: An optical component for optical communication having a smaller size and a shorter height. The optical component involves concave package 13 provided by layering ceramic substrates 131, groove section 19 formed at a bottom face of this package 13, optical semiconductor element 20 provided in this groove section 19, cover 12 provided to cover an opening section of package 13 and lens 11 formed at cover 12.

Abstract: The drop impact measuring system has i) a plurality of bimorph-type acceleration sensor containing a plurality of free vibrating sections each of which has individual draw-out electrodes; ii) a switch section for selecting output from the bimorph-type acceleration sensors; iii) an amplifying circuit for amplifying a signal applied via the switch section from the acceleration sensors; and iv) a logic circuit for logically evaluating the output from the amplifying circuit and controlling the switch section according to the result acquired from the logical evaluation.