Abstract: An optical system is disclosed which utilizes a pair of binary diffraction optic lenses to reprofile the intensity and the amplitude distribution profiles of a light beam prior to a rotating polygon mirror to profiles in the shapes of a sinc squared function and sinc function in order to generate a square pixel profile both in the intensity and amplitude at the photoreceptor plane. Both binary diffraction optic lenses have a plurality of segments. Each segment of the first binary diffraction optic lens either diverges, converges or passes through without a change, a portion of the light beam. The second binary diffraction optic lens, which is located down stream of the first binary diffraction optic lens, has an equal number of segments as the first binary diffraction optic: lens. Each segment of the second binary diffraction optic lens receives the light beam from a respective segment of the first binary diffraction optic lens and collimates the light beam.

Abstract: A new and improved decoder for decoding CCITT compressed image data. This decoder separates all the incoming codes into short codes and long codes. The short codes are sent to the short channel decoder and the long codes are sent to the long channel decoder. At each decoding cycle either the long channel decoder or the short channel decoder is active. The short channel decoder has a twin set decoder which decodes two short codes in parallel and guarantees two bits of decompressed data per decoding cycle. If the decoding of a first code generates a decompressed data of only one bit, then the decompressed data of a second code will be combined with the first decompressed data and the combination will be sent out. This process guarantees at least two bits of decompressed data per decoding cycle. The long channel decoder decodes the long intermediate codes which always generate at least four bits of decompressed data.

Abstract: A thermal ink jet printhead with a plurality of newly designed bubble containment chambers for reducing a spattering effect which is the ejection of unwanted small aerosol type droplets after the ejection of an ink drop. The printhead has one or more ink channels each having an opening at one end, known as nozzle, and also having a bubble containment chamber for each channel at a predetermined distance from the nozzle. The new bubble containment chamber is designed to absorb or redirect undesired acoustic waves produced from the collapse of a bubble in the bubble containment chamber which in turn causes the ejection of unwanted small aerosol type droplets after the ejection of an ink drop. The bubble containment chamber of this design absorbs or redirects the acoustic energy by having four different kinds of wedges on its walls.

Abstract: A new and improved decoder for decoding CCITT compressed image data. This decoder separates all the incoming codes into short codes and long codes. The short codes are sent to the short channel decoder and the long codes are sent to the Long Channel decoder. The short channel decoder has a twin set decoder which decodes two short codes in parallel and guarantees two bits of decompressed data per clock cycle. The Long Channel decoder decodes the long codes which always generate at least four bits of decompressed data. A look ahead logic determines the a0b1 and a0b2 relative distances for each of the next two codes to be decoded on the next clock cycle, while the current codes are in the process of decoding. The look ahead logic helps to increase the decoding speed.