Abstract: In this optical rotary encoder, detection tracks of a rotating disc are irradiated with detection light emitted from a light-emitting element. An optical signal obtained via slits in the detection tracks passes through a slit pattern in a fixed slit plate and is received by light-receiving surfaces of a light-receiving element. The slit pattern in the fixed slit plate is formed so as to fit into a range of an effective spot of the detection light. An LED or other light-emitting element that has a small effective spot diameter can be used, which is advantageous in terms of reducing costs and making the device more compact.

Abstract: In this optical rotary encoder, detection tracks of a rotating disc are irradiated with detection light emitted from a light-emitting element. An optical signal obtained via slits in the detection tracks passes through a slit pattern in a fixed slit plate and is received by light-receiving surfaces of a light-receiving element. The slit pattern in the fixed slit plate is formed so as to fit into a range of an effective spot of the detection light. An LED or other light-emitting element that has a small effective spot diameter can be used, which is advantageous in terms of reducing costs and making the device more compact.

Abstract: A rotation actuator comprises a motor and a planetary reduction gear device, and an internal gear of the planetary reduction gear device has an internal gear formation portion in which internal teeth are formed, a thin cylindrical portion, and an annular flange fixed to a device housing. An external peripheral surface portion of the cylindrical portion is used as a location for attaching a strain gauge, and a space on the inner side of the cylindrical portion is used as a location for mounting an angle detector for an input shaft. By concentrically arranging the strain gauge and angle detector, a rotation actuator that has a short axial length and is provided with the two types of detection mechanisms can be achieved.

Abstract: In an encoder signal interpolation divider (1) that automatically corrects errors in the offset and gain of an input signal at a high speed with a low cost circuit configuration, and can accurately generate an encoder signal having a predetermined resolution by interpolation division, analog input signals (A1, B1) are subjected to offset correction by a 0-point correction circuit (13) in adders (4, 5) prior to being digitally converted by A/D converters (8, 9), and are subjected to gain correction by an amplitude correction circuit (14) in amplifiers (6, 7). The corrected analog signals are converted to digital values, angle data is calculated in an angle data lookup table (10), and, based on these results, an encoder pulse signal having a predetermined resolution is generated and output from an encoder pulse signal generating circuit (12).

Abstract: A projection-type linear encoder has a moving grating plate formed with a set of photodiodes for detecting an origin position and a reflective grating plate formed with reflective grating sections for detecting an origin position. The set of photodiodes for detecting an origin position includes photodiodes (5Z, 5Z1, 5Z?, 5Z1?) that are aligned in accordance with an alignment pattern produced using random numbers, and the reflective grating sections for detecting the origin position include reflective grating sections and non-reflective grating sections that are wider than grating sections for detecting an A phase signal and a B phase signal similarly disposed in accordance with an alignment pattern produced using random numbers. The origin position of the moving grating plate can be precisely detected based on a differential signal of photodiodes (5Z) and photodiodes (5Z?) and a differential signal of photodiodes (5Z1, 5Z1?) that differ in phase by 90° to the photodiodes (5Z, 5Z?).

Abstract: In an encoder signal interpolation divider (1) that automatically corrects errors in the offset and gain of an input signal at a high speed with a low cost circuit configuration, and can accurately generate an encoder signal having a predetermined resolution by interpolation division, analog input signals (A1, B1) are subjected to offset correction by a 0-point correction circuit (13) in adders (4, 5) prior to being digitally converted by A/D converters (8, 9), and are subjected to gain correction by an amplitude correction circuit (14) in amplifiers (6, 7). The corrected analog signals are converted to digital values, angle data is calculated in an angle data lookup table (10), and, based on these results, an encoder pulse signal having a predetermined resolution is generated and output from an encoder pulse signal generating circuit (12).

Abstract: A projection-type rotary encoder is provided which has a light source, an object grating plate in which a substantially fan-shaped object grating for transmitting light is arranged at constant angular intervals in the circumferential direction, a rotary scale plate in which a substantially fan-shaped scale grating for transmitting light is arranged at constant angular intervals in the circumferential direction, and a photodiode grating plate in which a substantially fan-shaped photodiode photosensitive surface grating is arranged at constant angular intervals in the circumferential direction. A scale grating 32A is formed in the rotary scale plate with a shape and size that correspond to a light image of the object grating 31A incident on the surface thereof. A photodiode photosensitive surface grating 33A is formed in the photodiode grating plate with a shape and size that correspond to a light image of the scale grating 32A incident on the surface thereof.