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 mirror angle adjustment structure is provided for an optical system, such as a laser scanning unit. The structure comprises a support projection projected from a mirror support member at a position corresponding to an end along the lengthwise direction of the mirror, an adjustment screw member disposed at the other end of the mirror corresponding to another end across the mirror and passed through and threaded with the mirror support member from the side where the mirror is disposed, and an urging mechanism, such as a leaf spring, for urging the mirror towards the support projection and the adjustment screw member.

Abstract: A printer, for printing on continuous recording paper, includes tractors disposed in the recording paper feed path of the printer, with each of the tractors circumferentially travelling in synchronism with movement of the continuous recording paper when the tractors engage feed holes of the continuous paper. When no printing operation is performed, travel of the tractors can be prevented by operation of an electromagnetic clutch, or a combination of one way clutches. Further, the printer uses an electrophotographic method wherein when no printing operation is performed, a transfer charger or fixing roller can be retracted from an operational position. A lever, associated with movement of the transfer charge or fixing roller, is pressed against and locked with the pulley fixed to the rotating shaft of each of the tractors to thereby prohibit the movement of the tractor.

Abstract: In a laser scanning system for an electrophotographic imaging apparatus, a laser beam, emitted from a laser source, is deflected to repeatedly scan a predetermined angle zone. Before the scanning of the predetermined angle zone, the deflected laser beam is received by a light receiving member. A cover member, projected from a housing of the laser scanning system, covers the light receiving member in such a fashion that the incident of the deflected laser beam is prevented from entering at least an upstream side portion of the light receiving member. The cover member allows the light receiving device to receive the deflected laser beam at a position having a predetermined positional relationship with the laser source.

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.

Abstract: In a mirror-angle adjusting arrangement, at least one adjusting member is arranged between a surface formed on a mirror support structure and a mirror. The adjusting member is reciprocatively movable along the surface while contacting mirror in such a fashion that the angle of the mirror with respect to the surface varies upon movement of the adjusting member.

Abstract: A beam position detector, particularly for use in a scanned laser beam printer, in which the scanned beam is reflected by a mirror to a light sensor. In order to align the mirror, a mirror holder is rotatable on a base plate also holding the sensor. The mirror is also tiltable with respect to the base plate.

Abstract: An apparatus for adjusting light beam direction comprises, for instance, two prisms, i.e., a first and a second prisms arranged, in order, along an incident direction of light beam; an incident face of the first prism being parallel to a plane which is assumed to rotate an imaginary vertical plane perpendicular to the incident direction around a rotational axis by a first acute angle; an outgoing face of the first prism being parallel to a plane which is assumed to rotate the vertical plane around the axis by a second acute angle larger than the first one in the same direction as the latter; an incident face of the second prism being parallel to the outgoing face of the first prism and an outgoing face of the second prism being parallel to the incident face of the first prism, at the zero-adjusting state; and at least one of these prisms being able to adjustably rotate around the rotational axis.

Abstract: In a deflection scanning optical system, a single first mirror is arranged between a laser beam source and a surface to be scanned. The first mirror has a first reflecting section, a second reflecting section and a transparent section. The laser beam from the laser beam source is reflected by the first reflecting section. A second mirror is provided for reflecting the laser beam reflected by the first reflecting section, toward the second reflecting section. The second mirror also reflects the laser beam reflected by the first reflecting section to transmit the reflected laser beam through the transparent section, thereby directing the transmitted laser beam toward the surface to be scanned. A detector received the laser beam reflected by the second mirror toward the second reflecting section and reflected by the same, for detecting a scanning position of the laser beam with respect to the surface to be scanned.

Abstract: A cap adapted to be detachably mounted to a camera lens, for example, comprises a locking member movable radially of the body of the cap, grooves formed in the body, and a spacer mounted to the locking member. The locking member has engaging legs, which are fitted in the grooves and can be resiliently deformed within spaces. After the locking member has been mounted to the body, the spacer occupies the spaces and prevents the deformation of the legs.