Photonics Research Incorporated

Vixel Corporation

Greg R Olbright

Jack L Jewell

Stanley E Swirhun

Stephen D Walker

An on-airway breath-by-breath oxygen sensor is described which has the necessary low weight, fast response and high precision required for oxygen consumption measurement. A vertical-cavity surface-emitting laser (VCSEL) is continuously tuned to emit light at the resonance of oxygen, or more generally, the molecular species of interest. The light beam is directed through a sample containing the molecular species of interest onto a detector. The amount of light absorbed is approximately proportional to the concentration of the molecular species of interest in the sample.

Sensor for analyzing molecular species

The present invention is directed to an optical system which includes an image region having at least one light source which directs a beam of light along an optical axis and an object region which is adapted to receive the light from the light source. An optical delivery system is between the image region and object region. The optical delivery system receives the light from the image region and directs it to the object region. The optical delivery system is formed of a plurality of optical elements, such as lenses and volume holograms. The optical delivery system is designed to either receive a plurality of beams of light from a plurality of sources or different modes of a single light source and form a single spot of light in the image region having the combined power of all of the beams of light or modes of a single beam. The optical delivery system can also condense or expand the spacing between the beams of light from a plurality of light sources. The optical delivery system is designed so that the Lagrange invariant thereof at the object region is different from the Lagrange invariant thereof at the image region.

Optical beam delivery system

A phased array of semiconductor laser elements is provided in which the percentage of light which propagates into different diffractive orders is modified by an optical element. The diode laser includes a body of a semiconductor material having an active region therein which is adapted to generate radiation and emit the radiation form a surface of the body, and separate reflecting mirrors at opposite sides of the active region with at least one of the mirrors being partially transparent to the generated light to allow the light generated in the active region to be emitted therethrough. The optical element may take the form of a modification in the arrangement of the semiconductor laser elements, or an array of microprisms, or an external mirror to modify the percentage of light which propagates into different diffractive orders.

Phased array semiconductor laser

A vertical-cavity, surface-emitting semiconductor diode laser having a monolithic and planar surface and having lateral anisotropy in order to control the polarization of the emitted beam of light. The diode laser includes a body of a semiconductor material having an active region therein which is adapted to generate radiation and emit the radiation from a surface of the body, and a separate reflecting mirror at opposite sides of the active region with at least one of the mirrors being partially transparent to the generated light to allow the light generated in the active region to be emitted therethrough. The anisotropy may be provided by utilizing anisotropy in the atomic or molecular structure of the materials forming the laser, or by anisotropic patterning or deliberate offset alignment in processing of the laser or through anisotropic structures in the laser cavity to control the polarization of the emitted beam.

Polarized surface-emitting laser

A vertical-cavity, surface-emitting semiconductor laser having a substrate, an active layer of a semiconductor material which is adapted to generate light on a surface of the substrate, a pair of mirrors at opposite sides of the active layer and means for expanding the diameter of the output beam. Such means include a spacer layer of an optically passive material between the active layer and at least one of the mirrors, and mirror layers of reduced difference in index of refraction, interface layers having intermediate indices of refraction placed between mirror layers, in either case expanding the effective optical cavity length to at least 100 times the thickness of the active material in the active layer. Another means is anti-waveguiding which directly expands the diameter of the beam. The expanded cavity provides an output beam of larger diameter while maintaining stable single mode emission. The spacer layer may be a separate layer or region over the substrate or at least a portion of the substrate.

Growing community of inventors

Boulder, CO, United States of America

Greg R Olbright