Apparatus for controlling the quantity of light

Apparatus for controlling the quantity of radiation emitted by emitting means, comprising:

• means for generating variable driving power;
• radiation emitting means comprising a plurality of radiation emitting devices each for emitting radiation in response to driving power generated by said driving power generating means;
• detector means for detecting the emitted radiation from said emitting means and producing a detection signal corresponding to the quantity of detected radiation;
• selection means for selecting one of said plurality of radiation emitting devices to emit radiation in response to the driving power;
• means for making said detector means detect the radiation from said one selected device and controlling the quantity of the radiation emitted thereby in response to the driving power to a predetermined level;
• and
• means for applying a switching signal to said selection means to cause it to select another one of said radiation emitting devices.

Apparatus for controlling the quantity of radiation emitted by emitting means, comprising:

• means for generating a recording signal;
• radiation emitting means for emitting radiation modulated with a recording signal applied thereto by said generating means;
• photodetector means for receiving the emitted radiation from said radiation emitting means and producing a detection output corresponding to the received radiation;
• means for discriminating whether or not the duration time of said recording signal is longer than a predetermined time length;
• and
• means for controlling the radiation emitted from sid radiation emitting means when the duration of said recording signal is longer than said predetermined time as discriminated by said discriminating means to adjust said detection output to a predetermined value.

Apparatus for controlling the quantity of radiation emitted by emitting means, comprising:

• means for generating a driving signal;
• means for emitting radiation in response to a driving signal generated by said driving signal generating means;
• means for deflecting the emitted radiation from said radiation emitting means toward a recording medium;
• photodetector means for receiving the emitted radiation from said radiation emitting means and producing a detection output corresponding to the received radiation;
• means for producing a reference signal having a predetermined value;
• discriminating means for comparing said detection output with the reference signal to make a discrimination as to whether or not said detection output has a predetermined value;
• first control means for controlling said detection output in response to an output from said discriminating means in such a manner that said detection output can reach the predetermined value;
• and
• second control means for controlling said detection output in such a manner that when said detection output could not be adjusted to said predetermined value by said first control means, said detection output is brought to a preset value by said second control means.

Apparatus for controlling the quantity of radiation emitted by beam generating means, comprising:

• beam generating means for generating a plurality of front beams and a plurality of back beams projecting in the opposite direction to that of the front beams;
• means for deflecting said front beams toward a recording medium;
• photodetecting means disposed for receiving all of the back beams;
• selection and driving means for making said beam generating means emit selectively one of the front beams and the corresponding one of the back beams;
• and
• means for controlling said one back beam selected by said selection and driving means and received by said photodetection means so that the quantity of said received beams reaches a predetermined value.

Apparatus for controlling the quantity of radiation emitted by emitting means, comprising:

• means for generating driving power;
• means for emitting radiation in response to the driving power generated by said driving power generating means;
• detector means for detecting the radiation emitted from said emitting means and producing a detection signal corresponding to the quantity of the detected radiation;
• means for generating a signal for instructing the adjustment of the quantity of radiation emitted from said emitting means;
• means responsive to the instruction signal for gradually varying the driving power after bringing the driving power generating means to a predetermined level;
• and
• means for holding the driving power constant when the detection signal from said detector means reaches a predetermined value.

Recording device with apparatus for controlling the quantity of radiation emitted by emitting means, comprising:

• means for generating a light beam;
• recording means for recording information on a recording medium on a page-by-page basis by means of said light beam generating means;
• means for introducing timing signals generated after the end of one page recording and before the start of the next page recording;
• control means for bringing an intensity of the light beam generated by said light beam generating means to a predetermined value in response to the introduction of the timing signals;
• and
• hold means for holding the intensity of the light beam brought to the predetermined value with said control means.