Abstract: A light emitting diode exposure head for a recording apparatus which comprises an aligned assembly of a plurality of diode modules, each module including an array of said diodes and associated circuit boards mounted on a common base, the diode modules being supported in elevated position above the base, and interconnection circuit strips for the modules disposed on the base in partial overlapping relation beneath the margins of the elevated modules, the interconnection strips having a line of bonding pads for making wire-bonded connections with the circuit boards.

Abstract: A method is disclosed of adjusting the light-emission of a light-emitting diode to a predetermined output level for a given driving current. The light-emitting diode is irradiated with a laser beam in a manner to burn tiny holes in the light-emitting surface to such an extent that said predetermined output level is obtained. The invention furthermore comprises a method of obtaining a substantially uniform light output of an array of light-emitting diodes.

Abstract: A recording apparatus for linewise recording information on a moving photoreceptor, comprising a recording head with two staggered rows of pointlike radiation sources, wherein a shortcoming of prior art devices, namely stepwise deformation of a recorded line, caused by an incorrect registering of the even and uneven data dots, as a consequence of speed fluctuations of the photoreceptor upon recording, is overcome by controlling the recording of the data signals as a function of a signal from a speed sensor of the photoreceptor.

Abstract: In a recording apparatus comprising a recording head with a multiplicity of individually addressable and energizable point-like radiation sources arranged in staggered parallel rows for irradiating points across a moving photoreceptor, the driver circuits for the different rows of radiation sources are provided by identical chips. Each chip incorporates delay means capable of holding data-bit signals for a delay period before the signals are transmitted for energizing the associated radiation sources but is formed so that the delay means can be rendered inoperative by selecting one or other of different mode control voltage input points. The control chips for one row of the radiation sources are set in the delay-operative mode to compensate for the distance between the two rows of sources.

Abstract: A recording device for linearly recording information upon a moving photoreceptor using a recording head that can be manufactured more readily. The recording head is made with a plurality of modules, each module comprising LED chip means having an aggregate length (n) greater than the length (o) of the base plate of the module and projecting exteriorly of the module side edges, and a common integrated control circuit for all the LED's mounted on the base plate of a given module, the outputs of such circuit being connected by wire bonding to the respective LED's on the module.

Abstract: A recording apparatus for linewise recording information on a moving photoreceptor by means of a plurality of chips on each of which parallel sub-rows of uniformly spaced radiation sources are formed, wherein a shortcoming of prior art apparatus, namely the impossibility to use chips on which even one radiation source only is defect, is overcome.The apparatus comprises two parallel rows of radiation sources, each row comprising reserve radiation sources that are arranged with corresponding basic radiation sources of the other group in optical parallelism, and connection circuit means for establishing electrical contact with a basic and/or a reserve radiation source (FIG. 5).