US 11,681,228 B2
Method and apparatus for illuminating image points
Bernhard Thallner, St. Florian am Inn (AT); and Boris Povazay, Vienna (AT)
Assigned to EV Group E. Thallner GmbH, St. Florian am Inn (AT)
Appl. No. 16/973,578
Filed by EV Group E. Thallner GmbH, St. Florian am Inn (AT)
PCT Filed Jun. 19, 2018, PCT No. PCT/EP2018/066181
§ 371(c)(1), (2) Date Dec. 9, 2020,
PCT Pub. No. WO2019/242840, PCT Pub. Date Dec. 26, 2019.
Prior Publication US 2021/0247697 A1, Aug. 12, 2021
Int. Cl. G03F 7/20 (2006.01); G03F 7/00 (2006.01)
CPC G03F 7/704 (2013.01) [G03F 7/2051 (2013.01); G03F 7/70283 (2013.01); G03F 7/70291 (2013.01); G03F 7/70358 (2013.01); G03F 7/70466 (2013.01); G03F 7/70558 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for the exposure of image points of a layer comprising a photosensitive material on a substrate by means of an optical system, said method comprising:
continuously moving the image points with respect to the optical system; and
controlling a plurality of secondary beams by use of the optical system individually for individual exposures of each image point, whereby the secondary beams are put either into an ON state or into an OFF state,
wherein:
a) secondary beams in the ON state produce an individual exposure of the image point assigned to the respective secondary beam; and
b) secondary beams in the OFF state do not produce any individual exposure of the image point assigned to the respective secondary beam,
wherein, for the generation of image points with grey tones n>1; individual exposures are carried out by different secondary beams with individual doses D,
wherein the grey tone G of each image point is defined by the sum of individual doses D,
wherein the grey tones G are further defined by n individual exposures with different individual doses D due to a change in a radiation intensity of the secondary beams such that a relationship between the radiation intensity of the secondary beams and the sum of the individual doses D is nonlinear,
wherein the grey tone G of at least one of the image points is generated by:
superposition of the image points in a lateral direction based on intensity profiles of the secondary beams; and
means of successively arranged mirrors of a digital micromirror device, and
wherein a width of the intensity profiles is greater than or equal to a width of the successively arranged mirrors.