| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a focus system in which transmission with higher efficiency per plane is ensured at the time of holding symmetric pixels and a thermal medium having a lower sensitivity can be used. SOLUTION: The focus system comprises lens means (4, 5, 6) for focusing modulated light on a thermal medium and can focus the cross-section (3) of a light beam (2) emitted from a modulation plane (1) on the surface of the thermal medium. The lens means (4, 5, 6) can focus the cross-section (3) of the light beam (2) emitted from the modulation plane (1) on the surface while enlarging or contracting in the first direction (x) as compared with the second direction (y). Furthermore, a light modulated such that the surface is movable in the second direction (y) is focused on the thermal medium at least during an interval when the surface of the thermal medium is irradiated with a light beam (7) focused through the lens means (4, 5, 6).</p> |
