Abstract:
An image sensor unit includes a frame storing a linear illuminator that linearly illuminates a document, a rod lens array is used to form an image of light reflected from the document irradiated by the linear illuminator, and a printed circuit board on which a light-receiving sensor that converts light whose image has been formed by the rod lens array into an electrical signal is mounted. In the frame, a lens storage compartment, a linear illuminator storage compartment, and the linear illuminator are adjacently arranged substantially in parallel to each other in a longitudinal direction, with an inter-compartment portion formed in the frame interposed therebetween. At least one pin insertion opening is formed that extends from an inner wall of the lens storage compartment opposing the inter-compartment portion into an outside of the frame and through which a pressing pin is inserted, and in the inter-compartment portion, a face defining the lens storage compartment is formed as a vertical reference face with which a side plate of the rod lens array is brought into close contact for fixing. A notch used for applying an adhesive to the side plate of the rod lens array is disposed corresponding to the pin insertion opening and is formed to be open from the lens storage compartment to the linear illuminator storage compartment.
Abstract:
This invention is directed to an image printing apparatus which can print images without any halfway offset or obverse/reverse pixel offset at a low cost. An image printing apparatus includes a clock generating section which generates a dot clock as the basis of each pixel forming an image, an image printing section which prints a one-line image in a main scanning direction in accordance with image data with reference to the dot clock output from the clock generating section, and prints a one-page image by repeating in the sub-scanning direction one-line image printing performed in the main scanning direction, and a clock control section which changeably controls the frequency of the dot clock during scanning of one line in the main scanning direction.
Abstract:
An image forming apparatus includes a latent image forming unit in which a light beam scans in a second scan region wider than a first scan region. The light beam is modulated in accordance with an image signal within the range of the first scan region for every scanning cycle and guided onto the effective image region to form a line latent image. A write timing adjuster adjusts a write start position for writing a latent image along the main scanning direction, based on a time difference between a first detection signal output when a first light beam scanning away from the effective image region moves passed an optical sensor, and a second detection signal output when a second light beam scanning toward the effective image region moves passed the optical sensor.
Abstract:
An optical scanning apparatus provides improved image quality by changing the amount of writing scale compensation for a pixel clock during a scanning cycle. A pixel clock generation unit of the optical scanning apparatus divides the scanning cycle into multiple division periods. A phase change of the pixel clock is carried out for each of the division periods. The phase change can also be different from scanning cycle to scanning cycle.
Abstract:
Apparatus for fixing the position of an optical sensor within a range of motion in relation to an optical apparatus. The fixing apparatus provides permits a range of motion through five degrees of freedom (DOF) during the securing process. The apparatus includes a housing for the optical assembly, a middle bracket, with the middle bracket secured to the optical apparatus. The range of motion is provided by a gimbal design in the housing and middle bracket which creates the five DOF. There are no screws involved in the fixing process to impart torques or forces to the parts being aligned and secured in position. An ultraviolet (UV) activated adhesive is used to secure the sensor housing to the middle bracket and the middle bracket to the optical scanner housing. The middle bracket is formed of a material transparent to UV light, and a high percentage of the UV light can pass through it to cure the adhesive applied between the parts. A vertical hole runs through tabs of both the housing and the middle bracket. The adhesive is applied into this region where it is constrained by the parts. The adhesive is a liquid during the alignment process which allows relative motion between the parts. When alignment is complete, the adhesive region is exposed to UV light which cures the adhesive into a solid vertical column, creating a form of chemical rivet. This chemical rivet provides a very strong mechanical interlock of the components in addition to the adhesive bonding of the components.
Abstract:
A system and method for spatially matching the output of two imaging stations in an electro-photographic device by using a second order polynomial curve and a third order polynomial curve to approximate the non-linearity errors between the two imaging stations and using the second order polynomial curve and the third order polynomial curve to modify the frequency of a pixel clock.
Abstract:
An image forming apparatus comprises a light generator (e.g., laser) generating a scanning light beam and a driver driving the light generator depending on a drive signal to be provided. In this apparatus, data formed of image information at each pixel of each line along a main scan direction of an image to be targeted are distributed into a plurality of strings (i.e., channels) of data (e.g., two strings). Concerning each pixel provided by data in each string, information indicative of both a start and an end of modulation (e.g., PWM) is then produced. By using the start and end information, a modulator performs modulation depending on the data of each pixel in each string, providing a modulated signal. The modulated signals from the plural strings are mutually synthesized at synchronizes timings, being provided as the drive signal and given to the driver.
Abstract:
A method for calibrating a VCO within a phase locked loop circuit is disclosed. First, a DAC output voltage is set to its minimum, and a counter M is adjusted until a comparator is its threshold voltage. Next, the DAC is set to another voltage, and counter M is again adjusted to the comparator threshold. This process is repeated for as many steps as desired. When the phase locked loop circuit requests an instantaneous frequency, an interpolation of the requested frequency against the curve created by the above-described method gives the value required by the DAC.
Abstract:
An image is accurately recorded by a light beam on a PS plate wound on a drum which is rotating at a constant speed. A rotary encoder detects information of a recording position in a main scanning direction by the light beam that is emitted from an optical unit to the PS plate. Based on the detected information, a PLL circuit of a recording synchronizing signal generating unit generates an original clock. Pulses of the original clock are counted by a decimating counter, which outputs a decimating instruction to decimate a pulse from the original clock each time the count reaches a preset count. Based on the decimating instruction, a pulse is decimated from the original clock, and a decimated clock is frequency-divided at a fixed frequency-dividing ratio by a frequency divider, which outputs a pixel clock for recording the image. Since the frequency of the pixel clock is varied by decimating the original clock based on the preset count, the image can accurately be recorded on the PS plate by determining in advance the preset count depending on the positional relationship between the PS plate and the optical unit.
Abstract:
A method for adjusting a scanning module includes the steps of: providing a first fixing force to mount an adjustment assembly, to which an image sensor is attached, onto a base of the scanning module and loosely fixing the adjustment assembly to the base with a first fixing force; adjusting a relative position between the adjustment assembly and the base of the scanning module, and testing a first adjustment result until the first adjustment result is accepted; securing the adjustment assembly to the base of the scanning module with a second fixing force; and removing the first fixing force. The first and second fixing forces come from different sources.