The invention discloses an optical readout method utilizing a
fiber optics bundle to carrying out modulation, belonging to an application of
fiber optics in the technical field of optical readout type
infrared focal plane thermal imaging, and solving the problem of filtering difficulty due to inconsistent zero-order spectrums caused by different initial attitudes of the imaging units of the optical readout type
infrared focal plane array. The scheme can replace a knife edge (or an aperture) to carry out optical filtering; and meanwhile,
stray light generated due to limited environment conditions has better inhibitory action, thereby improving the quality of output images. The main process is as follows:
ray is transmitted in
fiber according to the total reflection principle; the fiber has rigid requirement on the incidence angle of the
ray, thus the
ray (such as the
stray light in environment) which does not satisfy the incidence angle can not be totally reflected in the fiber but is refracted into a cladding, i.e. the fiber
optics bundle can not transmit the ray, thereby inhibiting the
stray light; and the ray (such as beam expanding collimation
light source) satisfying the incidence angle can be transmitted to the rear end surface of the fiber optics bundle by means of the total reflection principle. When a focal plane array arranged on the rear end surface deflects because of being heated so as to change the angle of the ray entering the fiber from the end surface, thus the angle of the ray emitted from the front end surface also changes; and
luminous energy received from an optical
receiver changes and is embodied by the light and shade change on the image.