Apparatus and method for exposure of relief precursors

A method for exposing a relief precursor, said method comprising:

• a. placing a relief precursor between a first and a second light source;
• b. exposing the relief precursor with the first light source;
• c. moving the second light source whilst exposing the relief precursor with the second light source;
• d. absorbing at least a portion of the light emitted by the second light source and transmitted through the relief precursor, in a space between the first light source and the relief precursor;
• and
• e. removing the relief precursor from between the first and second light source.

An apparatus for exposure of a relief precursor which comprises a substrate layer and at least one photosensitive layer, said apparatus comprising:

• a first light source comprising a LED array configured to illuminate a first side of the relief precursor,
• a second light source configured to illuminate a second side of the relief precursor opposite the first side,
• a moving mechanism configured to cause a movement of the second light source relative to the relief precursor;
• and
• a controller comprising circuitry configured to process instructions for controlling the first light source and the second light source, wherein the controller comprises circuitry configured to process instructions is configured for correlating the intensity distribution of the light output by the LED array to the movement of the second light source relative to the relief precursor.

An apparatus for exposure of a relief precursor which comprises a substrate layer and at least one photosensitive layer, said apparatus comprising:

• a static first light source comprising a LED array configured to illuminate a first side of the relief precursor,
• a moveable second light source configured to illuminate a second side of the relief precursor opposite the first side,
• a moving mechanism configured to cause a movement of the second light source relative to the relief precursor whilst exposing the relief precursor with the second light source;
• and
• a controller programmed to execute instructions for controlling the moving mechanism, the first light source and the second light source, said controller further programmed to perform at least one of the following steps:
• adjusting an exposure timing of the first and second light source such that whilst the first light source exposes at a first power level, the second light source is moved multiple times back and forth so that each portion of the relief precursor has received the same dose at the end of the exposure by the first light source;
• and
• adjusting an exposure timing of the first and second light source such that, after a first exposure with the first light source and a first exposure with the second light source, a second or subsequent exposure with the first light source and a second or subsequent exposure with the second light source is performed.