Abstract: An optical focusing and collecting system includes: a first optical shaping portion, including an output surface, adapted to supply a primary light beam which is made annular; a second optical focusing and collecting portion, including a conical upper central reflective surface and a conical lower central reflective surface; a third optical return portion, including a reflective surface located between the output surface and the upper central reflective surface, along a main optical axis (?) and having transverse dimensions smaller than those of the annular primary light beam supplied by the first optical portion.

Abstract: A microwave tuned oscillator utilizing a ferromagnetic thin film resonator comprises: a) a microwave resonator (1) comprising a ferromagnetic thin film resonance plate (110) such as a disc-shaped YIG crystal placed on a microwave integrated circuit (11), such as a half-wavelength strip-line resonator, b) bias magnetic field means (12) for applying a bias magnetic field perpendicular to the ferromagnetic thin film resonance plate (110), c) an active element for oscillation (21), a reactive feedback element (24) and a load (23, 25) controlled by the microwave properties of the ferromagnetic thin film resonance plate (110) through a load feedback loop (4), and d) an overall positive feedback loop (3, 14, 15) connected between the active element for oscillation (21) and the microwave resonator (1) to cause a sustained oscillation to build up at one of parametrically excited resonances of the ferromagnetic thin film resonance plate (110).

Abstract: A microwave tuned oscillator utilizing a ferromagnetic thin film resonator comprises: a) a microwave resonator (1) comprising a ferromagnetic thin film resonance plate (110) such as a disc-shaped YIG crystal placed on a microwave integrated circuit (11), such as a half-wavelength strip-line resonator, b) bias magnetic field means (12) for applying a bias magnetic field perpendicular to the ferromagnetic thin film resonance plate (110), c) an active element for oscillation (21), a reactive feedback element (24) and a load (23, 25) controlled by Ihe microwave properties of the ferromagnetic thin film resonance plate (110) through a load feedback loop (4), and d) an overall positive feedback loop (3, 14, 15) connected between the active element for oscillation (21) and the microwave resonator (1) to cause a sustained oscillation to build up at one of parametrically excited resonances of the ferromagnetic thin film resonance plate (110).