Combined X-ray Image Plate Reader and Eraser with Light Barrier

The patent combines the readout device and erasing device into a single integrated system where the readout beam and erasing beam are generated by the same light source and detected by the same photodetector. The readout beam reads the latent image while the erasing beam simultaneously erases residual images, allowing both functions to be performed concurrently rather than sequentially, thus reducing the total time required while maintaining reliable erasure quality.

The patent employs wavelength-specific optical filtering where the readout beam uses a specific wavelength (e.g., green light) and the erasing beam uses a different wavelength (e.g., blue light). Optical filters are placed in front of the photodetector to allow only the readout wavelength to reach the detector during reading, while blocking the erasing wavelength. This wavelength separation with local optical filtering allows the erasing head to be positioned close to the reading head without causing light interference, as each functional area receives only its designated wavelength.

The patent changes the wavelength parameter of the erasing beam to match the absorption characteristics of the image plate material. By selecting a wavelength that is strongly absorbed by the phosphor material used in the image plate, the erasing process becomes highly efficient at removing residual images with minimal energy input. This wavelength optimization reduces heat generation while maintaining complete erasure, as the energy is efficiently converted to the desired erasing effect rather than being wasted as heat.