| 摘要 |
<p>The device for visually reconstructing one or more digital images displayed on a transparent liquid-crystal display (LCD) screen, comprises the following parts: a luminous source (1) on whose optical trajectory is positioned an LCD screen (15) for displaying the digital image by means of a central unit, an anti-heat filter (3), a set of filters (5) for the colours red, green and blue, a holographic diffuser (19), a field pupil or diaphragm (22), a collimator lens (8), an objective lens (25) for projecting the image onto a photosensitive paper (12), two linear polarizers (16,23) positioned in front of and behind the LCD screen, a field lens (17) positioned between the LCD screen and the front polarizer (23), and a displacement organ (24) for laterally shifting or displacing the LCD screen or each pixel so as to allow several expositions of the image displayed on the LCD screen. The LCD screen is equipped with a network of microlenses and a mask defining openings with respect to each constitutive cell of the LCD screen. The LCD screen is associated with a telecentric projection optics including the lenses (17,25) designed to increase the contrast and the uniformity of the images. An optical organ including the diffuser (19) and the pupil (22) induces the diffusion of the light beam and its adaptation with respect to the network of microlenses and the mask of the LCD screen. The diffuser (19) is placed in the focal plane of the collimator lens (8). The displacement organ (24) comprises a plate which is shifted in a controlled manner by piezoelectric means. The method is implemented by the device as claimed and comprises the steps of associating the LCD screen with the network of microlenses and the mask, utilizing the telecentric projection optics, controlling the angle (theta) of divergence of the incident beam, operating the lateral displacement of the LCD screen, and carrying one or more expositions for each displacement. The image is subjected to a redimensioning at the level of the central unit where the digital images are stored, and the image is divided in 4, 9, or 16 frames which can be displayed on the LCD screen. Each frame subjects three planes of the image, according to the colours red, green and blue, and the resultant image is obtained in colour by the method of additive synthesis.</p> |
