NOVELTY - A solar energy collecting device comprises two light guide (101) layers guiding light; photocell; diffractive features disposed to redirect ambient light incident on the first light guide layer; another diffractive features disposed to redirect ambient light incident on the second light guide layer; and solar thermal generator. The light is guided in the light guide layers to the photocell.    USE - Solar energy collecting device for producing power or heat a thermal generator to heat water or produce electricity from steam. Uses include but are not limited to: supplementing electrical power to home or business; recharging battery of vehicle powdered by gas and/or electricity; providing electrical power to laptop or handheld devices e.g. personal digital assistants or cell phones; lighting the vests and jackets worn by airline ground crew, police, fire fighters and emergency workers in the dark to increase visibility; providing power in planes, trucks, trains, bicycles, sailboats, satellites; and providing power in camping or back-packing trips.    ADVANTAGE - The device includes a light guide which realizes opto-electric devices that convert light energy into electricity with increased efficiency and lower cost; and is lighter, environmentally stable and robust and upgraded with relative ease.    DETAILED DESCRIPTION - The photocell is disposed laterally with respect to light collector(s). The solar thermal generator is disposed rearward of the light collector. The light collector transmits infrared radiation to the solar thermal generator. The photocell comprises a photovoltaic cell; and is butt-coupled to an edge of the light guide, or disposed at comer of the light guide, or embossed on the light guide. The first diffractive features are separated from the second of diffractive features. The light guides are flexible and comprise thin films. The first diffractive features comprise surface relief features. The diffractive features are formed in separate holographic layers comprising transmission holograms, and/or reflection holograms. An optical isolation layer is disposed between the two light guide layers to separate the diffraction features. The two light guide layers are laminated together to form parts of single light guide; and are disposed on automobile, aircraft, spacecraft; or nautical vessel; or bicycle, stroller, or trailer; or article of clothing; or shirt, pants, shorts, coat, jacket, vest, hat, or footwear; or computer, cell phone or personal digital assistant; architectural structure; house or building; electrical device; light, phone, or motor; or tent or sleeping bag. The light guide layers may be rolled-up or folded. The guide layers are greater than or equal to 1 cm2. Each light guide layer has a thickness of less than 500 mu m. Each diffractive feature is disposed in separate layers that are 1-100 mu m thick. The light collector can collect ambient light with an incident angle of - 45 degrees to 45?, preferably - 15 degrees to 15 degrees with respect to the normal to the surface of the light collector. An INDEPENDENT CLAIM is included for a method of fabricating a device for collecting solar energy.    DESCRIPTION OF DRAWING(S) - The drawing shows a side view of the light guide when a ray of light is refracted inside a light guide and is transmitted out of the light guide.    Light guide (101)    Rays (102i, 102r, 102t)