DYNAMIC RANGE OF A LINE SCANNER HAVING A PHOTOSENSITIVE ARRAY THAT PROVIDES VARIABLE EXPOSURE

摘要

A line scanner measures 3D coordinates of an object surface and includes a projector with a light source that projects a line of light at the object surface. The line scanner also has a camera with a 2D array of light sensors and electronics that controls the exposure and readout times of each light sensor, the exposure time being controlled in either rows or columns of the array in a non-sequential manner, the readout time being controlled in either rows or columns that are the same as the rows or columns whose exposure time is being controlled, each of the light sensors converts an amount of captured optical energy into a digital signal value, the captured optical energy being from a reflected line of light from the object surface. Further includes a processor that receives the digital signal values and calculates the 3D coordinates of the object surface.

主权项

1. A line scanner for measuring three-dimensional coordinates of a surface of an object, comprising:
a projector including a light source and a projector lens, the projector configured to project light from the light source through the lens as a line of light at the surface of the object; a camera including a photosensitive array and a camera lens, the photosensitive array including a two-dimensional array of light sensors, the array of light sensors having M rows and N columns, where M and N are integers, the camera further including control electronics configured to control exposure time of each light sensor in the array of light sensors and to control readout time of each light sensor in the array of light sensors, the exposure time of each light sensor in the array of light sensors being controlled in one of the rows and the columns of the light sensors, the readout time of each light sensor in the array of light sensors being controlled in the one of the rows and the columns, the exposure time of each light sensor in the array of light sensors being controlled such that the array of light sensors is controlled in a non-sequential manner, each of the light sensors in the array of light sensors configured to convert an amount of optical energy captured by each of the light sensors into a digital signal value, the optical energy captured by the light sensors being from a reflected line of light from the surface of the object, the reflected line of light being the projected line of light reflected from the surface of the object; and a processor configured to receive the digital signal values and to calculate two of the three-dimensional coordinates of the surface of the object therefrom.