This invention provides a contact laser encoding anti-theft lock, comprising: a key for generating a set of light signals with different pulse repetition frequencies; a signal processing module for receiving a set of optical pulse signals, in which the optical signals are converted to a set of voltage signals at different voltage values, and for comparing the voltage signals with a predetermined voltage (the voltage signals within the predetermined voltage range can be output as usual otherwise the output voltage is set to be zero); an electrically controlled lock, for opening or locking anti-theft doors according to the output voltage from the signal processing module; and a power supply for the signal processing module and the electrically controlled lock. The contact laser encoding anti-theft lock of this invention shows higher security and duplication of the keys is more difficult compared with prior anti-theft locks.

A method for determining a length of a span of electrically conductive material, comprising a first voltage measurement across the entire span, and a second voltage measurement across a constant-length segment of the span. The dual measurements allow the calculation of the span length in a manner that is robust to many disturbances including ambient temperature, material temperature, and material stress and fatigue.

A method for determining a length of a span of electrically conductive material, comprising a first voltage measurement across the entire span, and a second voltage measurement across a constant-length segment of the span. The dual measurements allow the calculation of the span length in a manner that is robust to many disturbances including ambient temperature, material temperature, and material stress and fatigue.

A position detection device, for detecting a change in relative position of a detection object with respect to a reference portion, includes: a base portion immovable with respect to the reference portion; a following portion deformable or movable following relative movement of the detection object with respect to the reference portion; an expandable and contractible member; and a heat flux detection section. The expandable and contractible member is provided between the base portion and the following portion, is made of a material expandable and contractible according to deformation or movement of the following portion, and generates heat during contraction and absorbs heat during expansion. The heat flux detection section is provided to be subjected to heat of the expandable and contractible member, and is configured to detect a heat flux that is a flow of heat between an inside and an outside of the expandable and contractible member.

An information processing apparatus includes an acquisition unit configured to acquire a first phase signal and a second phase signal that are acquired by measuring a rotation of a moving object, and a calculation unit configured to calculate a rotational angle by an iterative calculation so as to satisfy a relational expression bearing an arctangent. The relational expression bearing the arctangent uses a first cosine wave and a second cosine wave at a higher harmonic of the first cosine wave for the first phase signal, and a first sine wave and a second sine wave at a higher harmonic of the first sine wave for the second phase signal. The first phase signal and the second phase signal may, for example, be analog signals having a wave shape.

A rotary encoder system for registering the rotary angle position and/or angular speed of a rotary shaft which extends along an axis of rotation, including at least two optical marks at the rotary shaft, an optical sensor with a pixel matrix having pixel points, an imaging device for imaging each mark in a substantially axial direction on the pixel matrix as a mark image, and an evaluation device for reading and evaluating the pixel matrix in order to determine data in relation to the rotary angle position and/or angular speed. Further, the marks, the imaging device and pixel points are embodied in such a way that the mark images on the pixel matrix have at least the area of a pixel point, and the evaluation device is embodied to establish the location of the centroids of the mark images on the pixel matrix.

Disclosure is related to an optical sensor array apparatus. According to one embodiment of the invention, multiple sensor pixels are arranged as an array and forming a sensor array. Every comparator circuit is connected to one sensor pixel so as to calculate its energy state. A light source such as laser is installed in the apparatus. A control circuit is provided to recognize the sensor pixels' energy states for determining the spatial interference difference made by the reflected ray. The sensor array apparatus may be adapted to various surfaces since the light intensity and exposure time is able to be modulated as a compensation mechanism.

Disclosure is related to an optical sensor array apparatus. According to one embodiment of the invention, multiple sensor pixels are arranged as an array and forming a sensor array. Every comparator circuit is connected to one sensor pixel so as to calculate its energy state. A light source such as laser is installed in the apparatus. A control circuit is provided to recognize the sensor pixels' energy states for determining the spatial interference difference made by the reflected ray. The sensor array apparatus may be adapted to various surfaces since the light intensity and exposure time is able to be modulated as a compensation mechanism.

Disclosure is related to a light tracing method, and an apparatus thereof. According to one embodiment of the invention, the apparatus is such as an optical indexer. The method for determining a moving direction is performed based on an optical constructive or destructive interference pattern made by reflected lights received by a sensor chip. In particular, the coherent light may be preferably used in order to enhance the interference effect. In an exemplary embodiment, the method includes firstly the sensor pixels in the sensor chip receiving the reflected light, and calculating the energy. Next, within a time slot, the energy state of each sensor pixel can be calculated. A moving vector may be determined from a difference between the binary energy states of the adjacent sensor pixels. The binary energy state is based on a comparison between every sensor pixel and a statistic average within the sampling time slot.

Provided is a method for controlling an ultrasonic motor to reduce noise sounding during low-speed rotation in a surveying instrument adopting the ultrasonic motor for a rotary shaft, and a surveying instrument for the same. In a method for controlling an ultrasonic motor according to an aspect of the present invention, in a low-speed rotation range of an ultrasonic motor, a ratio of an acceleration period as a time of application of the drive signal in a control cycle is controlled, and a time to start the acceleration period is randomly shifted for each control cycle. In a method for controlling an ultrasonic motor according to another aspect, a time to start the acceleration period is regularly shifted for each control cycle. In a method for controlling an ultrasonic motor according to still another aspect, second-half acceleration control and first-half acceleration control are alternately repeated.