Abstract: Lens apparatus includes a TIR lens having multiple facets, the lens having a central axis about which the facets extend in non-circular relation. The lens may have a non-circular perimeter about that axis, and that perimeter may be rectangular or square.

Abstract: A TIR lens having a central axis, and toward which light from a light source is to be directed, and a light ray deviator positioned along the path of light travel between the source and the TIR lens, for deviating light rays toward portions of the lens spaced from the axis, thereby to more evenly distribute light flux at the output of the TIR lens.

Abstract: A radiant energy redirecting system comprising a radiant energy transmitting body structure; the structure comprising multiple elements, each of which acts as a radiant energy redirecting module, having on its cross-sectional perimeter an entry face to receive incidence of the energy into the interior of the perimeter, an exit face to pass the energy to the exterior of the perimeter in a direction towards the reverse side of the body from the side of the incidence, and a Totally Internally Reflecting face angled relative to the entry and exit faces to redirect towards the exit face the radiant energy incident from the entry face; the body structure generally redirecting incident radiant energy towards a predetermined target zone situated apart from and on the reverse side of the body relative to the side of the incidence; and lens structure associated with at least one of the faces for redirecting radiant energy passing between the entry and exit faces via the Totally Internally Reflecting face.

Abstract: A radiant energy redirecting system comprising a radiant energy transmitting body structure; the structure comprising multiple elements, each of which acts as a radiant energy redirecting module, having on its cross-sectional perimeter an entry face to receive incidence of the energy into the interior of the perimeter, an exit face to pass the energy to the exterior of the perimeter in a direction towards the reverse side of the body from the side of the incidence, and a Totally Internally Reflecting face angled relative to the entry and exit faces to redirect towards the exit face the radiant energy incident from the entry face; the body structure generally redirecting incident radiant energy towards a predetermined target zone situated apart from and on the reverse side of the body relative to the side of the incidence; and lens structure associated with at least one of the faces for redirecting radiant energy passing between the entry and exit faces via the Totally Internally Reflecting face.

Abstract: A diffuser based on a phase volume holographic medium is recorded non-holographically with speckle which define non-discontinuous and smoothly varying change in the refractive index of the medium. The diffuser scatters light traveling from an entrance surface to an exit surfaces and reflection from the diffuser is substantially limited to Fresnel reflection from the entrance and exit surfaces and light exiting the exit surface is substantially non-specular.

Abstract: A diamondlike carbon thin film protected hologram comprises an organic film deposited on a substrate and recorded to form a hologram, and a diamondlike carbon thin film deposited on the hologram, or first and second substrates having a diamondlike carbon thin film deposited thereon and an organic film having a holographic pattern recorded therein and sandwiched between the diamondlike carbon thin films of the first and second substrates. A method of fabricating a diamondlike carbon thin film protected hologram comprises forming a layer of dichromated gelatin on a substrate, recording the dichromated gelatin to form a hologram, and depositing on the hologram a diamondlike carbon thin film at room temperature, or depositing a diamondlike carbon thin film on first and second substrates, forming a layer of dichromated gelatin on the thin film of one of the substrates, recording the layer to form a hologram, and adhering the thin film of the second substrate to the hologram.

Abstract: A highly efficient combustor/reactor for a thermophotovoltaic process is provided.It includes:(a) an insulated combustion chamber containing a combustion zone,(b) first and second beds of refractory particles exposed to that zone,(c) structure for supplying a first combustion reactant to that zone,(d) structure for flowing a second combustion reactant to the zone via one of the beds during time T.sub.1 and via the other of the beds during time T.sub.2,(e) structure for removing combustion products from the zone via the other of the beds during time T.sub.1, and via the one bed during time T.sub.2,(f) and thermophotovoltaic cell apparatus exposed to heat radiated from the zone.

Abstract: A non-intrusive thermal power monitor and method for determining the amount of sensible heat withdrawn from or added to a fluid stream flowing in a conduit by an unknown source includes a thermal power transfer device that supplies or removes a known amount of heat energy to the fluid in a conduit. First and second temperature sensors sense the temperature of the fluid stream across the thermal power transfer device, and this information is used to determine a heat capacity rate of the fluid in the fluid stream. Additional non-intrusive temperature sensors sense the temperature of the fluid stream as it passes through and across a thermal power sink or heat source and provides a temperature differential. These temperatures are processed in a control circuit, and the thermal power added to or extracted from the fluid stream is determined in the control circuit by multiplying the measured temperature differential by the heat capacity rate of the fluid stream.

Abstract: A radiant energy redirecting system comprises:(a) a radiant energy transmitting body means,(b) said means comprising multiple elements, each of which acts as a radiant energy redirecting module, having on its cross-sectional perimeter an entry face to receive incidence of said energy into the interior of said perimeter, an exit face to pass said energy to the exterior of said perimeter in a direction towards the reverse side of the body from the side of said incidence, and a Totally Internally Reflecting face angled relative to said entry and exit faces to redirect towards said exit face the radiant energy incident from said entry face,(c) said body means generally redirecting incident radiant energy towards a predetermined target zone situated apart from and on the reverse side of said body relative to the side of said incidence.