Abstract: In an optical linear encoder, light from an LED 2 passes through a moving grating 31 formed in a semiconductor moving plate 3 and is reflected by a reflective grating 41 of a reflective grating plate 4. An image of the reflective grating is detected by photodiodes 32 that are formed in the shape of a grid on the semiconductor moving plate 3. The moving grating 31 and the photodiodes 32 are formed on the same semiconductor substrate with the photodiodes 32 in the form of a grid having a lens effect. Consequently, a lens optical system is not required, making it possible to produce a compact, small-scale encoder. A differential signal for an A-phase signal obtained from a group of photodiodes arranged on the semiconductor substrate and an inverse of this signal is produced as the A-phase signal, and a differential signal for a B-phase signal and an inverse of this signal is produced as the B-phase signal, so that an encoder output with little error can be obtained.

Abstract: In a projection encoder based on a triple-grating concept, a light-transmitting grating group 3 for detecting A- and B-phase signals, a photodiode group 4 for detecting A- and B-phase signals, and a photodiode group 5 for detecting a home position are formed on a movable grating plate 6 of a projection linear encoder 1; and a reflecting grating group 7 for detecting A- and B-phase signals, and a reflecting grating group 8 for detecting the home position are formed on a reflecting grating plate 9.

Abstract: To provide a small and lightweight optical switching element with a simple structure capable of fast response, and an optical switching apparatus employing the optical switching element. Optical extraction unit contacts an upper substrate with electrostatic attraction generated between a transparent electrode of the optical extraction unit and a transparent electrode of the upper substrate. In the case that light enters one V-shaped trench of the upper substrate vertically, the light enters the optical extraction unit of the upper substrate and is emitted from a back of the optical extraction unit (a tapered unit). Subsequently, the incident light P1 passes through a lower substrate and is converted into transmission light. With electrostatic attraction generated between a transparent electrode of the lower substrate and a transparent electrode of the optical extraction unit, the optical extraction unit is attracted to a lower substrate side.

Abstract: A micro-mirror for deflecting an incident light is disclosed, wherein the micro-mirror comprises: a mirror section for reflecting an incident light issued from a laser diode; a hinge section including a fixed section and a movable section each having a flat surface; and a drive section having a bi-morph structure made of two or more of materials having different heat expansion coefficient for deflecting said mirror section to change relative angle to said incident light.

Abstract: To make an optical switch smaller, two frames are formed by etching in such manner that when they are stuck together to form a support member, an hexagonal opening appears. The end portions of a pair of fixed optical fibers are arranged in the bottom portions of a pair of opposing V-grooves provided in this hexagonal opening. A pair of movable optical fibers are fixed at the other end of the support member, and these movable optical fibers are arranged in such manner that their end faces are contiguous with the end faces of the pair of fixed optical fibers. A drive mechanism causes the end portions of this pair of vertically arranged movable optical fibers to move to the left or the right, come into contact with the walls of respective V-grooves, slide into the bottoms of the grooves, and thereby have their cores aligned with the cores of the fixed optical fibers.

Abstract: In an optical linear encoder, light from an LED 2 passes through a moving grating 31 formed in a semiconductor moving plate 3 and is reflected by a reflective grating 41 of a reflective grating plate 4. An image of the reflective grating is detected by photodiodes 32 that are formed in the shape of a grid on the semiconductor moving plate 3. The moving grating 31 and the photodiodes 32 are formed on the same semiconductor substrate with the photodiodes 32 in the form of a grid having a lens effect. Consequently, a lens optical system is not required, making it possible to produce a compact, small-scale encoder. A differential signal for an A-phase signal obtained from a group of photodiodes arranged on the semiconductor substrate and an inverse of this signal is produced as the A-phase signal, and a differential signal for a B-phase signal and an inverse of this signal is produced as the B-phase signal, so that an encoder output with little error can be obtained.

Abstract: If a semiconductor device employing semiconductor light-receiving elements is disposed on a single optical axis, laser light which is incident on these light-receiving elements is interrupted by the semiconductor device, and it will be impossible to confirm as a whole that the alignment of a multiplicity of components disposed over a distance has been correctly adjusted. This problem is overcome by using a semiconductor light-receiving element with a structure which absorbs only some of a received laser light beam and which allows the greater part of the beam to be transmitted to its rear face.

Abstract: To provide a small and lightweight optical switching element with a simple structure capable of fast response, and an optical switching apparatus employing the optical switching element. Optical extraction unit contacts an upper substrate with electrostatic attraction generated between a transparent electrode of the optical extraction unit and a transparent electrode of the upper substrate. In the case that light enters one V-shaped trench of the upper substrate vertically, the light enters the optical extraction unit of the upper substrate and is emitted from a back of the optical extraction unit (a tapered unit). Subsequently, the incident light P1 passes through a lower substrate and is converted into transmission light. With electrostatic attraction generated between a transparent electrode of the lower substrate and a transparent electrode of the optical extraction unit, the optical extraction unit is attracted to a lower substrate side.

Abstract: The hinge (13) should preferably be formed to have a higher resistance than ever against the pivoting of the mirror body (12) to effectively prevent the hinge (13) from being damaged. By adopting a suitable one of a variety of production steps as necessary, the hinge (13) can be formed more finely and with a higher precision and thus the micro mirror unit can be produced more easily in a shorter time. To this end, the hinge (13) is formed from a different material, such as SiNx, from the mirror substrate material from which the frame (11) and mirror body (12) are formed.

Abstract: The amount of the light beam passing through two diffraction gratings is output as an electrical signal by a photo detector. The amount of relative displacement of the diffraction gratings is detected according to the electric signal (output signal) that changes in proportion to the relative displacement. Groove portions and ridge portions are alternately arranged on the first diffraction grating, through which the light beam passes and undergoes wavefront modulation by mutual interference of the zeroth-order diffracted light. This eliminates interference of the zeroth-order diffracted light with a diffracted light of another order, and eliminates changes in the fundamental wave component of the output signal caused by changes in the gap between the two diffraction gratings. The output signal can be made not to include a high-order component by a predetermined modification to at least one of either the array pitch or width of a transparent portion in the second diffraction grating.

Abstract: A scale and encoder are capable of stably outputting a displacement signal with less distortion. The scale has grating pattern lines arranged successively, and the widths of the pattern lines of a second scale are not P/2 but are determined to remove high-order distortion components on the grating pattern. For example, for removing the third and fifth order distortion components, the scale is made to include two slits in which pattern line widths are 17P/30 and 23P/30.

Abstract: A first laser beam is modulated at a modulation frequency and focused on a first point in the proximity of a connection being tested so as to generate a photothermo elastic wave thereat, and a second laser beam is focused on a second point in the proximity of the connection, which second point is separated from the first point. The second laser beam is scattered at the second point. A detector detects a modulation-frequency component of the scattered second laser beam, so as to detect a propagated level at the second point of the photo-thermo elastic wave from said first point based on the detected modulation-frequency component of the scattered second laser beam. The propagation of the elastic wave depends on the strength of the connection and the detected level of the elastic wave indicates strength of the connection.