Image or pattern transfer optical system for thermal dye transfer apparatus

Claim 1

In a continuous tone thermal dye transfer apparatus in which a web of dye carrying donor is moved along a predetermined path in relation to a receiver sheet and wherein dye from the donor is transferred by sublimation from the donor to the receiver to form dye image in the receiver, an image or pattern transfer system comprising: (a) a laser which is energizable to produce a beam of light; (b) means including a collimating lens and a focusing lens for focusing light from the energized laser diode onto a predetermined area on the donor; (c) a liquid crystal display disposed between the collimating lens and the focusing lens and adapted to produce an image or pattern and arranged so that such beam illuminates the image or pattern as it passes through the display; (d) said donor including (i) a heat absorbing layer which absorbs heat from each focused light spot, and (ii) a layer having dye embedded in a binder, arranged so that heat absorbed by the heating absorbing layer is transferred to the dye layer in a sufficient amount to cause dye to sublime and transfer from the donor to the receiver to form the image or pattern; and (e) control means responsive to image signals representing the image or pattern for causing the liquid crystal display to display a desired image or pattern.