Abstract: Disclosed is a scanning apparatus having a cascade scanning optical system.

Abstract: Disclosed is a scanning apparatus having a cascade scanning optical system.

Abstract: A cascade scanning optical system which includes a plurality of laser scanning optical systems each emitting a laser beam to scan a surface of a member, and a beam splitter positioned in an optical path between the plurality of laser scanning optical systems and the member such that a first laser beam which has passed through the beam splitter and a second laser beam which has been reflected by the beam splitter proceed to the surface on a common line thereon in respective ranges of the common line. Each of the plurality of laser scanning optical systems is desinged as a telecentric system.

Abstract: A laser scanning device emits a scanning laser beam which scans a predetermined surface to be scanned to form an image consisting of a plurality of pixels on the surface. The laser scanning device determines the intensity of the laser beam for each pixel of an image to be formed, and executes a feed-back control of the laser diode so that the intensity of the laser beam for each pixel accurately corresponds to the gradation level thereof.

Abstract: A laser scanning unit emits a laser beam for scanning a surface within a predetermined scanning range. The laser scanning unit has a laser diode, and a laser diode controller for controlling the laser diode to emit the laser beam. The laser beam has an intensity set in accordance with image data corresponding to one of a plurality of predetermined graduation steps within an intensity range defined by a first intensity and a second intensity greater than the first intensity. The laser scanning unit is further provided with a first adjusting system for adjusting the first intensity to become a first predetermined intensity, and a second adjusting system for adjusting the second intensity to become a second predetermined intensity. One of the first adjusting system and the second adjusting system is actuated during each scanning operation, and are actuated alternately during successive scanning operations.

Abstract: A cascade scanning optical system which includes: a pair of laser scanning optical systems each having a laser beam emitter and a laser beam deflector, wherein a laser beam emitted by the laser beam emitter enters the laser beam deflector so that the laser beam deflector deflects the laser beam to scan a surface of a member such that the laser beams proceed to the surface on a common line thereon in respective ranges of the common line; a pair of mirrors respectively provided in the pair of laser scanning optical systems, each of the pair of mirrors being positioned in a corresponding optical path between the laser beam deflector and the member to reflect a laser beam incident thereon toward the surface; a pair of cylindrical lenses having power in a sub-scanning direction, respectively provided in the pair of laser scanning optical systems, each of the pair of cylindrical lenses being positioned in a corresponding optical path between the laser beam emitter and the laser beam deflector; first means for adjus

Abstract: A cascade scanning optical system which includes a first laser scanning optical system for emitting a first laser beam to scan a surface of a member to generate a first scanning line, and a second laser scanning optical system for emitting a second laser beam to scan the surface to generate a second scanning line, wherein the first and second laser scanning optical systems are arranged so as to combine the first scanning line with the second scanning line at a point of contact therebetween in a main scanning direction to form a single scanning line, and wherein each of the first and second laser scanning optical systems is designed as a non-telecentric system through which the incident angle of a corresponding one of the first and second laser beams relative to the surface varies in accordance with a variation in the position of a scanning spot of the corresponding one of the first and second laser beams on the surface in the main scanning direction, and further wherein an incident angle of each of the first

Abstract: A laser scanning system in which a laser beam is emitted by a laser source and repeatedly deflected by a deflector, such as a polygon mirror. A photo sensor is provided to detect the position of the deflected laser beam. The photo sensor and the laser source are mounted on a common support member so that the laser beam, deflected by the polygon mirror, directly enters the light receiving portion of the photo sensor. Optionally, a reflection mirror is provided such that the deflected laser beam is reflected by the reflection mirror and further deflected to the photo sensor by the polygon mirror.

Abstract: A light intensity control circuit for an optical scanning device in which an intensity of a beam emitted by a laser diode, is modulated in accordance with an image signal. The image signal includes information about gradation levels of an image to be formed by the scanning device on a photoconductive surface. A first control circuit sets a first intensity value of the beam corresponding to a minimum gradation level of the image to be formed, and a second circuit sets a second intensity value of the beam corresponding to a maximum gradation level of the image to be formed. A driving circuit drives the laser diode such that the intensity of the beam is determined in accordance with the image signal and a difference between the first intensity value and the second intensity value.

Abstract: In a power controlling device for laser emitting apparatus, a laser diode and a photodiode are provided. Current is generated by the photodiode in accordance with the intensity of laser beam received. The current flows across a resistor to generate a voltage, which is compared with a reference voltage. There is further provided a circuit for generating the reference voltage, which includes a pulse signal generating circuit in which a duty cycle of the pulse signal is changeable, and a voltage generator which generates voltage in accordance with the duty cycle of the pulse signal. The laser diode is driven in accordance with the result of comparison of the voltage generated by the resistor with the reference voltage which is adjusted in accordance with the duty cycle of the pulse signal.

Abstract: A laser beam emitting device is provided for use, for example, in a laser beam printer. The device includes a single laser diode for emitting a laser beam having an output power level that is dependent on a driving current supplied to the laser diode. Two laser diode drivers are connected to the single laser diode and can be individually energized to drive the single laser diode to emit a laser beam that can have different output power levels. A selector is connected to the drivers for producing one of a plurality of selecting signals corresponding to the different output power levels, respectively, to select and energize one of the drivers.

Abstract: A laser beam controller having a laser beam emitter for emitting a laser beam and a beam receiver which receives the laser beam emitted from the laser beam emitter and outputs a light receipt signal corresponding to a signal level of the laser beam. The laser controller includes a reference signal outputting device for outputting a reference signal in accordance with an environmental humidity of the laser controller. A comparator compares the light receipt signal of the light receiver with the references signal. A control device controls the output of the laser beam emitter in accordance with the comparison result of the comparator.

Abstract: A photodetector, for use as a scanning light beam detector in an optical scanner, has a light-detecting element having a light-detecting surface for detecting a scanning light beam. The photodetector has a slit film which has a light-transmissive section for allowing light to be applied to the light-detecting surface and a light-blocking section for blocking light from the light-detecting surface. The slit film is disposed directly on the light-detecting surface. The slit film is evaporated or printed directly on the light-detecting surface. Therefore, the scanning light beam is applied to a desired light-incident area of the light-detecting surface which is positioned and dimensioned with high accuracy. The slit film needs no complex procedure for fine positional adjustment as it is fixedly positioned with respect to the light-detecting element.