| abstract |
In, for example, a thermal imager with an infrared detector array 1, increased resolution is obtained by optically shifting the position of the image on the array by less than a pixel in the horizontal and/or vertical directions by means of a microscan assembly 4a, 4b. The latter comprises at least one element in the form of a segment of a solid of revolution which is rotatable about the axis 5 used to generate the solid so that it periodically covers the array 1 to stepwise shift the incident image, e.g. to produce line interlace. Oppositely shaped segments may be used to shift the image in opposite directions and they may be interleaved by other wedge shaped elements (4c, 4d, figure 8) for producing shifts in an orthogonal direction. Rotation of the elements may be synchronised with a chopper (they may be mounted thereon). <IMAGE> |