Abstract: A collimated laser beam is directed towards the wafer bottom such that the impinging light is partially forward deflected along the vias' bottom edges. Concentric laser interference fringes occur on the wafer top from constructive and destructive interference between the forward deflected and directly through propagating laser. A top down optical image from a number of vias' top openings and a top down fringe image from the same vias' concentric fringe sets are processed to three dimensionally characterize the vias.

Abstract: The invention discloses a non-imaging reflecting surface optimized for concentrating solar energy onto a high efficiency solar cell. It provides for accurate mapping of solar radiation from the reflector to the cell. Additionally it provides for using only that portion of the surface that participates in the radiation transfer and it creates substantially uniform radiation intensity on the cell surface. The uniformity applies to both the spectral and the intensity distribution of the radiation on the cell. The reflecting surface is an off-axis parabolic surface trimmed to include only ray intercepts that travel to the solar cell surface. The solar cell is located off-focus so that rays from the reflector intercept the cell surface according to a predetermined mapping.

Abstract: An optical non-contact measuring probe for measuring small changes in distance to a target comprises a laser diode (12) coupled to a projecting fiber (14), a receiving fiber (32) spaced a fixed distance from the projecting fiber, and a linear array (36) spaced a fixed distance from the emitting face (34) of the receiving fiber. Light is projected from the projecting fiber to a small area on the target. Light rays reflected from the target are collected by the receiving fiber at an angle and are carried by the receiving fiber by total internal reflection through the emitting face to the linear array where it is detected as a circle having a diameter ?D. The distance from the probe to the target can be measured as inversely function of the diameter ?D.

Abstract: An optical non-contact measuring probe for measuring small changes in distance to a target comprises a laser diode (12) coupled to a projecting fiber (14), a receiving fiber (32) spaced a fixed distance from the projecting fiber, and a linear array (36) spaced a fixed distance from the emitting face (34) of the receiving fiber. Light is projected from the projecting fiber to a small area on the target. Light rays reflected from the target are collected by the receiving fiber at an angle and are carried by the receiving fiber by total internal reflection through the emitting face to the linear array where it is detected as a circle having a diameter &phgr;D. The distance from the probe to the target can be measured as inversely function of the diameter &phgr;D.

Abstract: The mechanism of the present invention provides jet sprays of mixed water and air which continuously sweep up and down the spine of the user as he/she sits in the spa. The jets undergo a partial rotation about pivots in arcs of about 1/4 or 1/3 of a circle and then reverse and return. These arcs of spray direct the spray directly against the user's back in their midpoint of rotation and obliquely at the end points. Thus, the pressure of spray as felt by the user is continuously changing. This motion is accomplished by an impeller and worm gear arrangement which converts the energy of the water which is flowing to the jets.