摘要:
A light beam is used to illuminate a spot on a lens element which is shifted along the optical axis of an imaging system for auto-focus or optical zoom purposes. The light beam is arranged such that the reflected light beam from the lens element encounters a spot on the image sensor. The spot location on the image sensor is determined by a signal processor. As the lens element is shifted along the optical axis, the spot location changes accordingly. Based on the moving distance of the spot, the signal processor determines the shifting distance of the lens element and hence the position of the lens element. Based on the shifting distance of the lens element, a control module is used to adjust the lens position along the optical axis to achieve the desired focusing or zooming effects.
摘要:
A portable device (1) having an optical engine (16) adapted to form an image from an image source in four different modes to allow a viewer to view the image. The image source is a microdisplay device, which can be reflective (32), transmissive (32’) or emissive (32’’). The display modes include a near-eye display (NED) mode, a near projection display (NPD) mode, a Window mode that provides a virtual image to a viewer at a distance, and a projection display mode that projects an image on a surface at a distance. The portable device has an internal light source (20) to provide illumination to the image source for the first three modes. The portable device is further adapted to receive the light output from an external light source for use with the fourth mode.