Abstract: A beam position sensor for a beam scanner is disclosed for use in a laser printer. The printer comprises three diode lasers each of which emits at a different wavelength. The beams from the three lasers are combined by the use of dichroic plates to form one combined beam. The combined beam is scanned onto a receiving medium by a polygon. The beam position sensor of the present invention is adapted to sense the position of the polygon in order to provide a synchronizing signal which will insure that each raster line in the printer is started at the proper position. The beam position sensor includes a diode laser and optics for projecting a beam from the laser onto the polygon. The beam is reflected back from the polygon into a photodetector which effects the start of a new raster line at the appropriate time.

Abstract: A beam position sensor for a beam scanner is disclosed for use in a laser printer. The printer comprises three diode lasers each of which emits at a different wavelength. The beams from the three lasers are combined by the use of dichroic plates to form one combined beam. The combined beam is scanned onto a receiving medium by a polygon. The beam position sensor of the present invention is adapted to sense the position of the polygon in order to provide a synchronizing signal which will insure that each raster line in the printer is started at the proper position. The beam position sensor includes a diode laser and optics for projecting a beam from the laser onto the polygon. The beam is reflected back from the polygon into a photodetector which effects the start of a new raster line at the appropriate time. In order to minimize the number of optical elements in the beam position sensor and to simplify the device, the diode laser and the photodetector are located along the same optical axis.

Abstract: A laser printer is disclosed which is adapted to be used for color imaging. The printer comprises three diode lasers, each of which emits at a different wavelength. Each laser beam is passed through an apodizing mask to trim the final spot size. The beams from the three lasers are combined by the use of dichroic mirrors to form one combined beam. The combined beam is shaped by two spherical mirrors and is scanned onto a receiving medium by a polygon. The receiving medium is sensitive to the infrared, and the diode lasers are selected to obtain the widest possible spectral separation in the light beams from the lasers.

Abstract: Beam intensity controlling device includes an acoustooptic cell which receives an input light beam and produces an undiffracted or zero-order light beam and a diffracted beam in response to an RF signal at a predetermined frequency. An error signal is produced which is a function of the differences in the intensity of the zero-order beam from a desired level. This error signal is used to control the amplitude of the RF signal which in turn changes the intensity in the diffracted and zero-order beams such that the zero-order beam intensity is maintained relatively constant and can be provided as an input to a modulating device. The error signal has two components, a DC component which corrects for slow drift of the zero-order light beam intensity and an AC component which corrects for higher frequency changes in the zero-order light beam intensity.

Abstract: A conductive strip for attachment to an aircraft radome to provide protection against the effects of a lightning strike to the radome, wherein the conductive strip has a series of holes formed in it.