LED bar array high addressable imaging in 2-dimensions
View Patent ↗An imaging apparatus includes an input that receives a stream of image pixels such as high addressable bits, multiple bits per pixel or binary image bits representing an input image and a processor that processes and directs signals to an LED bar that selectively exposes areas of a photoreceptor. The exposed areas of the photoreceptor form a latent image, controlled by the processor, of areas of varied exposure based on surrounding pixels. The processor examines the pixels to determine an image structure beneficially adaptable to varied exposure and selects a pixel for varied exposure, such as increased or decreased exposure or altered timing to apply the pixel.
1. A method of xerographic digital imaging where an LED bar selectively exposes an area of a photoreceptor in response to an input, the method comprising:
receiving a plurality of pixels represented by input pixel values;
identifying within the received pixels a pattern, the pattern including a transition between two different input pixel values; and
rendering the transition with a series of consecutive exposures of the photoreceptor by the LED bar, said exposures including: a first exposure at a first intensity level, a second exposure at a second intensity level greater than the first intensity level, a third exposure at a third intensity level less than the first intensity level, and fourth exposure at a fourth intensity level less than the third intensity level.
2. A method of digital imaging where a digital image is processed and output on a printing device including an image bar disposed across a charge retentive surface, the method comprising:
parsing an input data sequence representative of the digital image until a determined condition is encountered, the determined condition including a boundary offset in a process direction; and
assigning a varied exposure value to a datum in the input sequence based on adjacency to the determined condition, said assigning including:
assigning a value representative of increased electrostatic exposure relative to a reference value to a first datum in the input sequence at a position in the boundary; and
assigning a value representative of decreased electrostatic exposure relative to a reference value to a datum in the input sequence adjacent to the first datum.
3. The method of printing a digital image as set forth in claim 2 , where the converting comprises:
illuminating a portion of the charge retentive surface with:
a first spot size for data assigned with the reference value, and
a second spot size smaller than the first spot size for data assigned with the varied exposure value.
4. The method of imaging as set forth in claim 2 , where the parsing comprises template matching the input data sequence representative of the digital image.