A code disk is adapted to an optical absolute rotary encoder. The code disk is divided into a plurality of columns, with the plurality of columns disposed in a circumferential direction around a center position and respectively extending in a plurality of radial directions. The code disk comprises a plurality of disk sectors sequentially disposed in the circumferential direction around the center position, wherein each of the disk sectors comprises a plurality of code pieces, each of the code pieces comprises an encoded value, each of the encoded values comprises a plurality of bits adopting Manchester code, these bits are arranged in one of the radial directions, and the encoded values of two of the disk sectors are arranged as Gray code.

An angle measuring device includes first and second component groups and a bearing. The first component group includes a scale element having first and second graduations. The second component group has a first modular unit, having a position sensor, a second modular unit, having first to sixth position transducers, and a compensation coupling. To determine the relative angular position between the component groups, the first graduation is scannable with the aid of the position sensor. Using the first to third position transducers, the first graduation or a further graduation disposed on the scale element is scannable to determine a displacement of the scale element in a plane. Using the fourth to sixth position transducers, the second graduation is scannable to determine tilting of the scale element about a tilting axis, the position sensor being situated in a torsionally stiff but axially and radially flexible manner relative to the position transducers.

A linear guide includes a guide carriage (1) arranged on a guide rail (2) so as to be longitudinally displaceable, and comprising a length measuring device (5) provided on the guide rail (2) for determining a position of the guide carriage (1), which length measuring device has two measuring heads (6) and two tracks (7, 8) arranged side-by-side on the guide rail (2), each of which tracks is assigned to one of the measuring heads (6). Each of said tracks (7, 8) has a plurality of dimensional measures (9, 14) arranged one behind the other along the track (7, 8), wherein in an overlapping region (x1, yn, z1), the dimensional measures (9, 14) of both tracks (7, 8) overlap each other.

In order to provide an optical encoder with high resolution, the optical encoder includes: a rotary scale provided with a grating pattern having a first radial pattern and a plurality of concentric circular patterns disposed at predetermined intervals; and a light receiving element which detects a first interference fringe formed by the first pattern having a first period in the circumferential direction, a second interference fringe which is diffracted in a direction of the first interference fringe by a grating pattern having a second period in the circumferential direction disposed at a different radial position so that the second interference fringe has a period closer to the first period than the second period.

There is provided an operating method of an optical positioning system including: capturing an image frame of a detected surface, which has interleaved bright regions and dark regions, using a field of view and a shutter time of an optical sensor; counting a number of edge pairs between the bright regions and the dark regions that the field of view passes; calculating an average value of the image frame; calculating a ratio between the calculated average value and the shutter time; determining that the field of view is aligned with one of the dark regions when the ratio is smaller than a ratio threshold; and determining that the field of view is aligned with one of the bright regions when the ratio is larger than the ratio threshold.

A rotary coding disc and a method for designing the same is applied to an optical encoder. N-bit De Bruijn sequences include 1 and 0. The N-bit De Bruijn sequence has the maximum binary code and the minimum binary code. When a binary code having M bits is located between the maximum binary code and the minimum binary code, the corresponding N-bit De Bruijn sequences are selected as diagonal De Bruijn sequences, wherein

[00001]$\frac{2^N-2N}{2}-\frac{N}{2}<M<\frac{2^N-2N}{2}+\frac{N}{2}.$

The De Bruijn sequence may be converted into a De Bruijn energy level. The total number of 1 consecutively neighboring 0 and (N−1) consecutively neighboring N of the De Bruijn energy level is calculated. The transparent areas and the opaque areas are located based on the De Bruijn sequence or the De Bruijn energy level that corresponds to the total number less than or equal to N.

An optical position-measuring device includes a scale and a scanning unit. The scale is connected to a first object, extends along a measurement direction and includes a first track having an incremental measuring graduation, and a second track having an absolute measuring graduation. The scanning unit is connected to a second object and includes a light source, a detector having an absolute detector arrangement configured to detect an aperiodic light pattern transmitted from the absolute measuring graduation onto a detection plane and an incremental detector arrangement configured to detect a periodic light pattern transmitted from the incremental measuring graduation onto a detection plane, and a fiber-optic plate arranged as a continuous component in front of the absolute detector arrangement and the incremental detector arrangement, wherein both absolute track information and incremental track information in the respective detection planes are transmitted via the fiber-optic plate in this manner.

An encoder system includes a configurable detector array, wherein the configurable detector array includes a plurality of detectors. The encoder system may also include a memory operable to store a partition map that defines a state for each of the plurality of detectors. The encoder system may also include an emitter operable to generate a flux modulated by a motion object, wherein the configurable detector array is operable to receive the flux and generate respective current outputs for each of the detectors in response to the flux. In an embodiment, the current outputs from detectors having a same state are grouped together. The encoder system may also include one or more current duplicators to duplicate the current outputs from detectors having one state to group with the current outputs from detectors having a different state. The encoder system may also adjust weights of the current outputs.

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.

A rotary encoder for a valve comprises a rotatable code plate and an optical detector module comprising one or more optical detectors. The code plate defines a set of voids arranged along a set of one or more concentric circular arcs about an axis of rotation. The voids define an angle-dependent pattern over the set of arcs, the pattern comprising a plurality of distinct sectoral elements (A-O, X). At least two of the sectoral elements, located in non-adjacent sectors of the code plate, are identical, but the pattern is non-repeating over a single full rotation of the code plate about the axis. Each optical detector is aligned with a respective concentric circular arc of the code plate. A controller processes time-varying output signals from the optical detectors to determine successive positions of the rotatable code plate.