NOVELTY - The device has a focusing plate (103) which comprises focusing elements (114) to collect incident light and provide focused light beam out of bottom surface. Light guide (101) comprises light redirectors to receive focused light beam from corresponding focusing element and redirect received light beam towards photovoltaic cell (PV) (105) along edges of light guide. First actuator changes gap distance between light guide and focusing plate so as to place light redirectors in different relative position with respect to focal length of focusing elements.    USE - Sun-tracking solar energy harvesting device used in aerospace and satellite applications and building-integrated photovoltaic (BIPV) product such as window, roof, skylight, door or faade for providing electricity to residential and commercial properties and electronic device such as laptop, personal digital assistant (PDA), wrist watch, calculator, cell phone, camcorder, still and video cameras, and MP3 player, charging vehicle or watercraft batteries, and power navigational instrument, pumping water and solar thermal generation.    ADVANTAGE - The light collector that generates PV power while simultaneously providing illumination from received incident light is configured to efficiently collect light incident at noon when sun is overhead and sunlight is incident at angles closer to surface normal of the light collector as well as in the mornings and evening when light is incident at non-normal angles. Thus sunlight or ambient light is able to be collected, concentrated, and directed to PV cells in devices that convert light energy into electricity with increased efficiency. The PV cells are used only at the edges of the light guide, so that the cost of BIPV product is significantly reduced.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a transmissive light-collecting device.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of light collector.    Light guide (101)    Focusing plate (103)    PV cell (105)    Forward and rearward surfaces (112,113)    Focusing elements (114)