Abstract: Optical assemblies are provided in which an optical element is centered in the cavity of a barrel. The optical element is secured between a seat in the cavity and a retaining ring. The retaining ring has ring threads complementary to the barrel threads. The retaining ring has an abutment surface engaging a peripheral mounting edge of the optical element along a circular edge contact line. In some embodiments, the abutment surface has a frustro-spherical profile having a radius of curvature selected in view of the thread angle to maintain a centering of the optical element even when the retaining ring is decentered in the cavity. In other variants, the abutment surface has a frustro-conical profile having an inclination angle with respect to the center axis of the cavity selected in view of the thread angle to maintain said centering.

Abstract: Optical assemblies are provided in which an optical element is centered in the cavity of a barrel. The optical element is secured between a seat in the cavity and a retaining ring. The retaining ring has ring threads complementary to the barrel threads. The retaining ring has an abutment surface engaging a peripheral mounting edge of the optical element along a circular edge contact line. In some embodiments, the abutment surface has a frustro-spherical profile having a radius of curvature selected in view of the thread angle to maintain a centering of the optical element even when the retaining ring is decentered in the cavity. In other variants, the abutment surface has a frustro-conical profile having an inclination angle with respect to the center axis of the cavity selected in view of the thread angle to maintain said centering.

Abstract: An image projector comprises a plurality of flexible reflective analog modulators (FRAMs), an illumination optics for focusing at least one light source thereon, a conversion optics for converting the variations in divergence of the beams reflected therefrom into variations in intensity, and a scanning mechanism coupled to a projection optics for displaying an image, constructed of intensity modulated light dots or pixels, on a screen. FRAM curvatures, responsible for determining the divergence of the reflected beams, and ultimately the intensity of each pixel, are varied by an actuation voltage that can be modulated using waveforms that minimize the FRAM response times. For multicolor images, three laser light sources operating at different wavelengths are used in conjunction with three linear FRAM arrays.

Abstract: An image projector comprises a plurality of flexible reflective analog modulators (FRAMs), an illumination optics for focusing at least one light source thereon, a conversion optics for converting the variations in divergence of the beams reflected therefrom into variations in intensity, and a scanning mechanism coupled to a projection optics for displaying an image, constructed of intensity modulated light dots or pixels, on a screen. FRAM curvatures, responsible for determining the divergence of the reflected beams, and ultimately the intensity of each pixel, are varied by an actuation voltage that can be modulated using waveforms that minimize the FRAM response times. For multicolour images, three laser light sources operating at different wavelengths are used in conjunction with three linear FRAM arrays.