US 5,635,976 A · Method and apparatus for the production of a structure by focused laser radiation on a photosensitively coated substrate

Abstract

A system for writing geometric structures on a photosensitive substrate including a modulated laser beam source, a focusing lens, a deflector for producing a scanning action between the light source and the lens, and a device for mechanically moving the surface relative to the laser beam. Compressed data for use in writing the geometric structures is read out of a memory into a data delivery circuit such that the data is formatted to have both beam power and position information. A modulator logic circuit operates to call up the data from the data delivery circuit, form a modulation drive signal based on the power information, and delay the modulation drive signal based the position data. The modulator logic circuit thus operates to vary the modulation drive signal to begin or end exposure along the scan lines with greater resolution or pixel density by at least a factor of four more than the resolution or spacing density between adjacent scan lines. The scan lines are arranged within stripes, and adjacent stripes preferably are made to overlap such that the stripes are blended in the overlap according to a predetermined stepwise changing function.

Claims26

Dependent claims

A method of producing on a substrate a surface pattern for which the position and dimension of fundamental forms thereof are to be controlled in incremental steps that are substantially smaller than the dimension of the smallest fundamental form, the method comprising the steps of:

scanning with a laser beam along parallel scan lines arranged at approximately equal spacing from each other on the substrate;
and
controlling intensity of said laser beam while scanning, wherein the step of controlling the laser beam intensity includes
establishing a regular train of clock pulses with a predetermined clock period between the pulses,
establishing beam intensity data in a digital format for an edge of the pattern,
establishing beam position data in a digital format,
converting the beam position data to an equivalent time for positioning the laser beam along the scan line during scanning, the equivalent time being an integer number of clock pulses plus a fractional remainder,
creating a timing pulse corresponding to the equivalent time by counting the integer number of clock pulses digitally and adding a time delay for the fractional remainder, and
using the timing pulse to actuate the setting of the laser beam intensity according to the beam intensity data.

6 more elements

Dependencies are inferred from the claim text.

Method and apparatus for the production of a structure by focused laser radiation on a photosensitively coated substrate

Life of this patent

Method and apparatus for the production of a structure by focused laser radiation on a photosensitively coated substrate

Life of this patent

Abstract

Claims26