A sun-powered smoking pipe with a lens suspended by two arms, whose arms hold the lens at a fixed distance from the pipe's bowl, the distance being equal to the focal length of the lens. The arms have equal lengths and swivel in tandem both at their attachment points to the lens and at their attachment points to the pipe so that the entire device can be folded flat quickly. The only calibration required by a user is to rotate the lens so that the focal point is aimed inside the bowl when the lens is held in the direction of the sun.

A structure and method for utilizing natural light indoors or in the interior in a moving space are disclosed. The structure includes: at least one natural light condenser configured to reflect the natural light; a natural light transmitter configured such that the natural light reflected by the at least one natural light condenser is moved to the natural light transmitter; a smart lamp unit including an artificial light generator; a smart lamp driver located adjacent to the smart lamp unit and configured to move the smart lamp unit; and a controller connected to the at least one natural light condenser, the natural light transmitter, the smart lamp unit, and the smart lamp driver so as to transmit and receive information therewith. The controller is configured to combine artificial light with the natural light in response to a user request signal to radiate a combination of the artificial and natural light.

An optical see-through glass type display device comprises: an image projector projecting a virtual image; a first optical element configured to guide light of the virtual image; and a second optical element having a first reflection surface for reflecting back light coming through the front surface of the second optical element and a second reflection surface for retro-reflecting light coming through the rear surface of the second optical element. The second optical element is switchable between a first state in which the reflection on the first and second reflection surfaces is enabled and a second state in which the reflection on the first and second reflection surfaces is disabled.

An optical device and systems using an optical device are provided, where the optical device may be configured for collimating incoming light rays. The optical device may include a host medium substantially comprised of a transparent material and an array of substantially transparent structures embedded within the host medium. The structures of the array each include a convex side presented to the incoming light rays and a concave side that passes light rays through toward the output face of the host medium, collimating the rays. Multiple stages of arrays may be provided in the optical device, typically with lengthening aspect ratios and increasing indexes of refraction in a direction from the input face toward the output face. The systems may use the optical device for using an exterior light to illuminate an interior space in a building or to generate power.

An example optical device for backlighting includes a receiver disposed in a mobile device to receive ambient light. The optical device also includes a concentrator to concentrate the received ambient light received through the receiver. The optical device further includes a channeler to direct the ambient light beneath a surface of the mobile device to a digital display of the mobile device.

A sun-powered smoking pipe with a lens suspended by two arms, whose arms hold the lens at a fixed distance from the pipe's bowl, the distance being equal to the focal length of the lens. The arms have equal lengths and swivel in tandem both at their attachment points to the lens and at their attachment points to the pipe so that the entire device can be folded flat quickly. The only calibration required by a user is to rotate the lens so that the focal point is aimed inside the bowl when the lens is held in the direction of the sun.

A photoplethysmograph device includes a housing provided with a mounting hole; an optical device accommodated in the mounting hole; and a light-transmitting member including a central portion and a surrounding portion disposed around the central portion. The surrounding portion includes at least one end face having a textured layer configured to scatter and/or absorb light; the central portion has an end face without being provided with the textured layer. The light-transmitting member is connected with the housing and located at an outer side of the optical device. The end face of the central portion is disposed corresponding to the optical device, and the end face of the surrounding portion is disposed corresponding to an area without being provided with the optical device. The end face of the central portion near the optical device protrudes from the end face of the surrounding portion near the optical device

An optical product comprising a base member and an optical multilayer film formed directly on or indirectly above a film formation surface of the base member. The optical multilayer film reflects light on a short wavelength side and suppresses reflection of light on a longer wavelength side than the light on the short wavelength side, and has a first layer to an eighth layer counted from the base member side, the first layer is a first Al layer, the second layer is a first low-refractive-index layer, the third layer is a first high-refractive-index layer, the fourth layer is a second low-refractive-index layer, the fifth layer is a second Al layer, the sixth layer is a third low-refractive-index layer, the seventh layer is a second high-refractive-index layer, and the eighth layer is a fourth low-refractive-index layer.

A device for converting electromagnetic radiation into electricity comprises an expander that includes a conical shape having an axis and a curved surface that is configured to reflect electromagnetic radiation away from the axis to expand a beam of the electromagnetic radiation; and one or more energy conversion components configured to receive a beam of electromagnetic radiation expanded by the expander, and to generate electricity from the expanded beam of electromagnetic radiation. With the expander's curved surface, a beam of electromagnetic radiation that is highly concentratedhas a large radiation fluxmay be converted into a beam that has a larger cross-sectional area. Moreover, one can configure, if desired, the curved surface to provide a substantially uniform distribution of radiation across the expanded cross-sectional area. With such an expanded beam the one or more energy conversion components can efficiently convert some of the electromagnetic radiation into electricity.

An optical device and systems using an optical device are provided, where the optical device may be configured for collimating incoming light rays. The optical device may include a host medium substantially comprised of a transparent material and an array of substantially transparent structures embedded within the host medium. The structures of the array each include a convex side presented to the incoming light rays and a concave side that passes light rays through toward the output face of the host medium, collimating the rays. Multiple stages of arrays may be provided in the optical device, typically with lengthening aspect ratios and increasing indexes of refraction in a direction from the input face toward the output face. The systems may use the optical device for using an exterior light to illuminate an interior space in a building or to generate power.