摘要:
A laser beam scanning optical apparatus which has Moire fringes generating elements which is located near a position optically equivalent to a scanning surface and modulates a laser beam emitted from a laser source to generate Moire fringes. The Moire fringes generating elements comprises, for example, a first filter which has spatial grating and a second filter which has spatial grating which slants slightly with respect to the spatial grating of the first filter, the first filter and the second filter being arranged upstream and downstream respectively in an optical path. The laser beam scanning optical apparatus further has a light receiving element for receiving the Moire fringes generated by the Moire fringes generating elements. Focusing means for correcting a position of an image point of the laser beam is driven in accordance with an output of the light receiving element. For example, the light receiving element is a photoelectric element with a plurality of light receiving surfaces, each of which generates an electric signal in accordance with the laser beam incident thereto, and from a phase difference between the electric signals, the position of the image point is detected.
摘要:
A laser beam scanning optical apparatus has a focusing lens having different optical powers in the main scanning direction and the sub-scanning direction, moving means for moving the focusing lens on an optical direction, detecting means for detecting a state of convergence of the laser beam on a scanned surface, and control means for adjusting the convergence position of the laser beam by moving the focusing lens via driving said moving means based on the detection result of the detection means. In the aforementioned construction, the state of the convergence of the laser beam on a scanned surface is adjusted in the main scanning direction and the sub-scan direction by moving the focusing lens in an optical axis. The focusing lens is moved to a position of optimum convergence based on the construction of the optical system by detecting the state of convergence in the main scan direction and the sub-scan direction via a detecting means.
摘要:
A laser beam scanning optical apparatus which images and scans a laser beam emitted from a laser diode on a photo-sensitive drum through a focusing lens, a polygon mirror and an f.theta. lens. An SOS photosensor detects the scanned laser beam and generates a detection signal. The laser diode is controlled to perform pulse emission a specified time after the generation of the detection signal. The pulse beam is incident to a beam detector which adopts a knife edge method, and the amount of a focal shift is detected. The focusing lens is moved along the optical axis in accordance with the detected amount of a focal shift to correct the position of the image point.
摘要:
A laser beam optical scanning device which focuses and scans a laser beam emitted from laser diode 1 in the arrow b direction on a photosensitive drum 40 via focusing lens 3, polygonal mirror 6, and f.theta. lens 7. The scanning laser beam enters a convergence state detector 10, which detects the amount of dislocation of the convergence position. The amount of positional change is calculated to correct the convergence position based on the detected amount of dislocation, and the focusing lens 3 is moved on the optical axis of the lens via motor 21 to correct the beam convergence position. When processing is executed to correct the convergence position in the intermediate zone of the image formign range and the calculated amount of positional change exceeds a limit value, a detection error is assumed, and the focusing lens 3 is moved an amount less than the limit value.
摘要:
The image forming apparatus provides a plurality of recording units to form images based on their respective image data, overlaying the images formed by the plurality of recording units on a single transfer member traveling in a predetermined direction, control means to sequentially cause registration patterns of predetermined shape to be formed by the plurality of recording units, and detecting means to detect each registration pattern on the transfer member in at least two locations in both the diretion of travel of the transfer member and a direction perpendicular thereto, and output non-integrated detection values.
摘要:
In a multibeam scanning optical apparatus of a type where two parallel lines are simultaneously scanned by two laser beams irradiated from two semiconductor lasers, stable images are formed on the scanned surface by the two laser beams and the cost is reduced. The two laser beams irradiated from the two semiconductor lasers are directed substantially in the same direction through a beam splitter and then shaped by a condenser lens into two luminous fluxes whose optical axes are substantially parallel to each other. In another arrangement, the semiconductor lasers are directly secured to a surface of the beam splitter by use of an ultraviolet setting resin.
摘要:
A laser beam scanning optical apparatus which has a laser source unit, a collimator lens, a cylindrical lens, a polygon mirror and a scanning lens with an f.theta. function. The collimator lens is a bifocal lens, and because of the bifocal collimator lens, a part of the laser beam is focused on a point before the surface of a photosensitive member, and another part of the laser beam is focused on a point after the surface of the photosensitive member. Also, the cylindrical lens can be a bifocal lens. In this case, even when the magnification ratio in the sub scanning direction is designed small, the focal length of the cylindrical lens does not have to be lengthened.
摘要:
A laser beam composite apparatus which combines more than three beams including a first beam having a first wavelength, a second beam having a second wavelength and polarized in a predetermined direction and a third beam having a second wavelength and polarized in a direction perpendicular to said polarized direction of said second beam. The laser beam composite apparatus combines the first beam and the second beam based on difference of wavelengths thereof and further combines the third beam based on difference of polarized directions thereof.
摘要:
A reading apparatus of the invention has a high resolution reading part, a low resolution reading part, holding means for holding both the reading parts so as to be movable along a document, and means for selecting both the reading parts. The reading apparatus performs by one set of the apparatus total four modes of low resolution reading with respect to a light-impermeable document, high resolution reading with respect to the light-impermeable document, low resolution reading with respect to a large-sized light-permeable document, and high resolution reading with respect to a small-sized light-permeable document, such as a photographic film.
摘要:
An image reading apparatus of the present invention enlarges and reads a small light-permeable document such as a photographic film. In the apparatus of the present invention, an image of a film is divided into strips and is projected on a part of a main-scanning direction of a line image sensor. The film is then moved in a direction corresponding to the main-scanning direction of the line image sensor, thereby reading the image of the whole area of the film.