Patent ID: 7212557

Claim:
A line light source for producing a laser beam, which is adapted to be expanded into a linear laser beam for use as stimulating rays for an image read-out operation for reading out a radiation image having been stored on a stimulable phosphor sheet, the line light source comprising: i) a semiconductor laser chip for producing the laser beam, ii) a package for accommodating the semiconductor laser chip therein, iii) a radiating window, which is fitted to the package and allows the laser beam having been produced by the semiconductor laser chip to pass therethrough, iv) an optical system, which expands the laser beam that has passed through the radiating window in a direction of a line sensor; and v) an anti-reflection film being coated on a surface of the radiating window, the anti-reflection film having a reflectivity of at most 1.0% with respect to a wavelength of the laser beam having be en produced by the semiconductor laser chip, wherein the anti-reflection film suppresses the non-uniformity in distribution of intensity of the laser light in the direction of the line sensor, which has passed through the optical system, and prevents the vertical streak-like non-uniformity in the image.