Increasing scanning resolution through driving system control

Abstract

A method of increasing the scanning resolution of a scanner through controlling its driving system. By suitably adjusting the timing relationship between motor pulses and exposure pulses, a low-resolution driving system can produce a high-resolution image with no additional production cost incurred.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of Invention[0002]The present invention relates to a method of controlling the scanning resolution of a scanner. More particularly, the present invention relates to a method of increasing the scanning resolution of a scanner through control of its driving system.[0003]2. Description of Related Art[0004]Due to the many recent advances in computer multimedia technologies, image-processing techniques have gone forward a giant step, leading to some innovative designs for computer peripheral products such as a scanner. In a few years' time, the scanner has developed from a palm-top device capable of scanning only black and white pixels to a full-color high-resolution scanning system. In general, the resolution of a scanner along the horizontal axis depends on the density of its charge-coupled device (CCD) while the resolution of the scanner along the vertical axis depends on the level of precision of its driving system.[0005]To increase resolutio...

AI Technical Summary

Benefits of technology

[0013]Accordingly, one object of the present invention is to provide a drive control system capable of increasing the scanning resolution of a scanner. The system operates by adjusting the timing relationship between motor pulse and shift gate clock pulse so that a low resolution driving system can achieve a high-resolution scanning.

[0014]A second object of the invention is to provide a driving system capable of increasing scanning resolution without increasing the production cost a scanner.

[0016]In a second embodiment, a method for increasing the scanning resolution of a scanner through controlling its driving system is provided. Motor pulse signals are supplied to the driving motor of the scanner. In addition, shift gate clock pulses are supplied to the charge-coupled device of the scanner. The motor pulses and the shift gate clock pulses are adjusted so that multiple motor pulses are emitted for every shift gate clock pulse going to the charge-coupled device.

Problems solved by technology

However, the cost of making a stepper motor with a small stepping angle is relatively high.

In addition, when the scanner is performing low resolution scanning operations, pulsing rate or pulse per second (PPS) of the stepper motor increases, leading to a low torque.

Low torque increases the probability of stepping loss, thereby resulting in distortion of the scanned image.

However, the image thus obtained is no longer the real optical resolution.

However, the minimum micro-step that can be driven is ultimately limited by the external circuit.

Moreover, when an ordinary step is subdivided into too many micro-steps, control becomes very difficult.

The outcome is that distortion of the scanned image is unavoidable.

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