Holographic digitizer illuminator with mutually variant wavelengths

Abstract

Systems and methods for generating multiple mutually variant wavelengths of coherent radiation for three-dimensional imaging of a physical object, such as a tooth, are disclosed. A single radiation source, such as a laser diode, emits coherent electromagnetic radiation. A highly dispersive optical element, such as an echelle diffraction grating, separates radiation having specific wavelengths from the emitted spectrum into distinct beams. Optical components, such as optical masks, mirrors, and lenses, select and orient desired beams to illuminate the object. Small changes in drive current or heatsink temperature of the radiation source similarly affect all wavelengths of the emitted spectrum, so the relative wavelength differences of the desired beams of radiation remain constant. This wavelength stability is useful for synthetic wavelength generation for digital holography and minimizes errors in object shape profile measurements at various scales. Use of a single radiation source also reduces system cost and complexity.