<title>Diffractive optics at Eastman Kodak Company</title>

Abstract

Diffractive optics allow for increased optical performance, decreased size and weight, and decreased systems costs in numerous applications. Many types of optics can be fabricated using diffractive surfaces which are not possible or not cost competitive, using standard refractive lenses. Diffractive optics technology has been developed at Kodak to the point where low cost, mass produced, plastic molded diffractive optics are available on a commercial basis for internal and external use. Rotationally symmetric, aspheric, refractive/diffractive hybrid lenses have been injection molded in 100,000 part test runs and the lenses demonstrated consistent quality throughout the test. In this paper we will discuss design, analysis and fabrication of diffractive optics for some typical applications. These applications include diffractive hybrid achromats for visual applications such as, fixed focus and zoom camera lenses, camera viewfinders, diffractively achromatized laser diode objectives, asymmetric anamorphic diffractive concentrating and spectral filtering lenses for a rangefinding and autofocus applications, the use of diffractive optics in high quality, grayscale laser writers for beam deflection and F(theta) lenses, the use of an array of diffractive elements as concentrating lenses that also separate the incident light into its component colors for CCD array applications. Examples of Kodak fabricated injection molded diffractive hybrid achromats will be analyzed for surface figure and optical performance. Diffractive laser beam deflectors and F(theta) lenses and their production as plastic molded parts will also be discussed. Finally, measurements of diffraction efficiency of molded diffractive optics fabricated at Kodak will be discussed.