Abstract: The invention proposes a Subpixel Scroll method, which optically shifts the position of the mirror elements to the projection axis by one subpixel size each, with an additional 45° mirror between DMD and projection optics. The 45° mirror is shifted by ¼ mirror element width by means of a controllable actuator. The size of this change of position and the time are synchronized in such a way by the position indicator signals of the scan sled that the mirror element seems to stand relative to the substrate surface element. This resetting is however not bound to the DMD-switching speed of 10 kHz. Among other advantages, the invention reduces the blur at the edge transition by the higher resolution and facilitates a higher scan velocity, whereby the scan velocity depends on the dynamics of the actuator, the effective UV-power of the UV-source and the sensitivity of the photosensitive polymer.

Abstract: The present invention provides an improved process and an apparatus for producing collimated UV radiation for exposing printed circuit boards. The process consists in shortening the optical length of the downstream optics by dividing the UV radiation over many radiation sources, and in distributing the UV radiation uniformly on the substrate by using a scanning slide.

Abstract: The invention proposes a Subpixel Scroll method, which optically shifts the position of the mirror elements to the projection axis by one subpixel size each, with an additional 45° mirror between DMD and projection optics. The 45° mirror is shifted by ¼ mirror element width by means of a controllable actuator. The size of this change of position and the time are synchronized in such a way by the position indicator signals of the scan sled that the mirror element seems to stand relative to the substrate surface element. This resetting is however not bound to the DMD-switching speed of 10 kHz. Among other advantages, the invention reduces the blur at the edge transition by the higher resolution and facilitates a higher scan velocity, whereby the scan velocity depends on the dynamics of the actuator, the effective UV-power of the UV-source and the sensitivity of the photosensitive polymer.