Chung Shan Institute of Science and Technology

Chung-Shan Institute of Science and Technology, Armaments Bureau, M.n.d

Ming Chen

Yi-Yuh Hwang

Chin-Der Hwang

Wen-Chen Huang

Shin-I Ma

Mau-Ran Wang

Guang-Sheen Liu

Mau Ran Wang

Yi Yuh Hwang

Shin I Ma

An image invariant optical speckle capturing device and method. A highly coherent light is used to illuminate a surface and is scattered by the surface, and is captured from the direction with a &#xb1;10&#xb0; from the angle of specular reflection. A light restrictive module is designed to confine the angular field of view of the sensor, when the speckle capturing device has a relative motion with respect to the surface, the speckle only move on the image but the shape and the intensity are almost keep constant, that is favorable for high accuracy optical pattern recognition and positioning.

Image invariant optical speckle capturing device and method

The present invention relates to a large area undistorted imaging apparatus for light speckles and a method thereof. The large area undistorted imaging apparatus for light speckles comprises a light-emitting device, a light-limiting module, and a sensor. The light-limiting module is adapted in front of the sensor, and includes a plurality of light-limiting members. The light-limiting members are arranged in a one- or two-dimensional array. When the light-emitting device emits light to an object surface, one or more rays of scattered light are produced. By means of the light-limiting module, said one or more rays of scattered light are limited, and a plurality of rays of diffraction light is produced. The plurality of rays of diffraction light within a certain angular field of view produced by a light-limiting member interferes with each other and produces a plurality of undistorted light speckles, and forms an array of light-speckle images on the sensor. Finally, according to the array of light-speckle images, a large-area and undistorted light-speckle pattern is given. Because the light-speckle pattern is undistorted and records the three-dimensional characteristics of the object surface, the undistorted imaging apparatus can be applied to computer mice, finger guiders, smart cards, three-dimensional fingerprint identification apparatuses, a machine tool or precise manipulator positioning systems.

Large areas undistorted imaging apparatus for light speckles and method thereof

Growing community of inventors

Tao-Yuan, Taiwan

Ming Chen