The relative amount of fluorescent photons in the marked tumors is determined in relation to the overall number of photons detected.

A laser light source illuminates a target area having an unknown sample producing luminescence emitted photons, scattered photons and plasma emitted photons.

A photon detector (6) detects photons emitted by the crystal (2).

The photons include poly-energetic photons detected by a radiation sensitive detector.

The SPECT imaging device includes a detector configured to detect photons, such as photons, that are projected onto it.

The detector (124) detects photons comprised within the radiation (406) and photon data indicative of the detected photons is generated.

A light source (130) delivers a pulse (140) to a photon emitter (110) and generates pairs of electrons and holes to emit photons (150-1X, 150-2X, 150-3X).

The photon source may emit photons of a selected wavelength or wavelengths.

Narrow-band signal photons are generated by selectively narrow-band-filtering the idler photons.

The LED chips generate light photons.

Fiber optics is a means of photon transfer to provide photons to a biological reactor.

A single illumination source illuminates the threat agent deposited on the substrate with a plurality of photons to thereby produce elastic scattered photons and Raman scattered photons.

Photons are continuously radiated from a person's clothing.

An accurate measurement of photons is necessary, and requires the use of single photon counters, as well as a single-photon sources and sources of photon pairs twins.

The unitary optical amplifier receives input photons and pump laser energy (307) and provides output photons that have the same spatial orientation and phase as the corresponding input photons.