Abstract: An assembly block (20) including an LED element (51), a control unit (52) that controls the LED element (51), and a housing (30) that holds the LED element (51) and the control unit (52) is provided. The housing (30) includes mechanical interfaces (32, 33) for mechanically connecting to the outside and is at least partially translucent. The control unit (52) includes a first functional unit (111) that stores, on receiving first data sets (D1) that include data for controlling the color of light to be outputted from the LED element (51) and a transfer command via the first electrical interface (79a) associated with the first mechanical interface (32), the first data set (D1) in a buffer (121) and outputs the stored first data set (DS1) in the buffer (121) together with the transfer command via a second electrical interface (79b) associated with the mechanical interface (33) on the second side.

Abstract: An assembly block (20) including an LED element (51), a control unit (52) that controls the LED element (51), and a housing (30) that holds the LED element (51) and the control unit (52) is provided. The housing (30) includes mechanical interfaces (32, 33) for mechanically connecting to the outside and is at least partially translucent. The control unit (52) includes a first functional unit (111) that stores, on receiving first data sets (D1) that include data for controlling the color of light to be outputted from the LED element (51) and a transfer command via the first electrical interface (79a) associated with the first mechanical interface (32), the first data set (D1) in a buffer (121) and outputs the stored first data set (DS1) in the buffer (121) together with the transfer command via a second electrical interface (79b) associated with the mechanical interface (33) on the second side.

Abstract: In an exposure apparatus for exposing a photosensitive medium using light-emitting elements, correction to account for environmental conditions at the time of exposure that change is performed by dynamically changing the value of current or voltage to be supplied to the LEDs. Thereby, control of exposure duration can be performed solely for expression of multi-gradation levels, so that a very high resolution is not required for the control of exposure duration. Therefore, it is possible to realize a low-price exposure apparatus capable of printing multi-gradation images. For exposure to a single color using a plurality of LEDs, the gradation level to be expressed by the individual LEDs is cyclically changed, so that the construction of gradation level control for each LED can be simplified. Further, since the LEDs can be used at substantially equal duties, the individual variation of LEDs does not evidently show. It is also possible to prevent an inconvenient incident where a particular LED deteriorates.