Two-dimensional light scanning apparatus
First Claim
1. A two-dimensional light scanning apparatus configured to deflect light from a light source and repeatedly scan the light in a predetermined pattern, the apparatus comprising:
- a deflector configured to drive at a resonance frequency in a main scanning direction and a sub-scanning direction different from the main scanning direction;
a position sensor configured to detect a scanning position of the deflector;
a resonance frequency predicting part configured to predict the resonance frequency of the deflector, based on position information obtained from the position sensor; and
a deflector drive control part configured to;
for drawing a Lissajous figure in which scanning trajectories of the deflector do not overlap with each other for one frame, store a plurality of pairs of respective frequency ratios of driving signals in the sub-scanning direction to driving signals in the main scanning direction, and respective phases of the driving signals in the sub-scanning direction with respect to the driving signals in the main scanning direction;
select one pair of a frequency ratio and a phase from among the pairs of the respective frequency ratios and the respective phases, based on the resonance frequency predicted by the resonance frequency predicting part; and
control the deflector with a driving signal based on the selected pair of the frequency ratio and the phase.
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Accused Products
Abstract
A two-dimensional light scanning apparatus includes: a deflector to drive at a resonance frequency in a main scanning direction and a sub-scanning direction different from the main scanning direction; a position sensor to detect a scanning position of the deflector; a resonance frequency predicting part to predict the resonance frequency of the deflector; and a deflector drive control part to: for drawing a Lissajous figure in which scanning trajectories of the deflector do not overlap with each other for one frame, store a plurality of pairs of respective frequency ratios of driving signals in the sub-scanning direction to driving signals in the main scanning direction, and respective phases of the driving signals in the sub-scanning direction with respect to the driving signals in the main scanning direction; select one pair of a frequency ratio and a phase; and control the deflector with a driving signal.
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Citations
4 Claims
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1. A two-dimensional light scanning apparatus configured to deflect light from a light source and repeatedly scan the light in a predetermined pattern, the apparatus comprising:
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a deflector configured to drive at a resonance frequency in a main scanning direction and a sub-scanning direction different from the main scanning direction; a position sensor configured to detect a scanning position of the deflector; a resonance frequency predicting part configured to predict the resonance frequency of the deflector, based on position information obtained from the position sensor; and a deflector drive control part configured to; for drawing a Lissajous figure in which scanning trajectories of the deflector do not overlap with each other for one frame, store a plurality of pairs of respective frequency ratios of driving signals in the sub-scanning direction to driving signals in the main scanning direction, and respective phases of the driving signals in the sub-scanning direction with respect to the driving signals in the main scanning direction; select one pair of a frequency ratio and a phase from among the pairs of the respective frequency ratios and the respective phases, based on the resonance frequency predicted by the resonance frequency predicting part; and control the deflector with a driving signal based on the selected pair of the frequency ratio and the phase. - View Dependent Claims (2, 3, 4)
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Specification