An indicator unit for use at the edge of airfield runways which produces a split beam of light, the interface of which may be adjusted to the required angle of flight path to guide incoming aircraft, the indicator unit comprising a support assembly having mounted therein at least two projection tubes, each projection tube housing a removable pre-aligned projector having a light source, a red-passing filter and a divergent lens disposed to produce the split beam of light.
A glide slope indicator system in which light from an incoming aircraft's landing light is shaped by spherical/cylindrical lens combination into a line image which strikes a linear photodiode array. By determining which photodiode in the array the center of the line image strikes, the glide slope angle can be determined. An appropriate signal is communicated to the pilot via a pair of indicator lights mounted on the runway depending upon whether the aircraft is above, below or on the desired glide slope angle.
A Raman spectroscopic apparatus utilizing a broad stripe semiconductor laser as the excitation light source is provided. The output spectrum of the semiconductor laser is narrowed and stabilized by an internal grating to provide high spectral brightness. A high throughput optical system is also disclosed for Raman scattering signal excitation and extraction, which takes full advantage of the high spectral brightness of the laser source.
A light emitting diode (LED) signaling apparatus for navigational aids is provided. The signaling apparatus comprises a plurality of high intensity LEDs with their output beams individually controlled by high precision optical beam transformers. The transformed LED beams are mixed in a predetermined manner by controlling the relative position, angular orientation, and other parameters of the LEDs to produce a desired illumination pattern.
A quickly deployable and reconfigurable light emitting diode (LED) lighting apparatus with high output intensity and precisely controlled beam property is disclosed for navigational aids. The lighting apparatus comprises an array of high intensity LED units with their light beams individually controlled by secondary optical systems. The transformed light beams mix in a pre-determined manner to produce an illumination pattern with desired intensity distribution. The LED lighting apparatus may further comprise a micro-controller, a plurality of sensor elements, and a wireless transceiver for remote monitoring and control. The lighting apparatus can be powered by rechargeable batteries for temporary or semi-permanent lighting. It can also be powered by standard power lines for permanent lighting.
