Abstract: This disclosure is directed at a method and device capable of producing polarization entangled photon pairs and accomplishing polarization insensitive wavelength conversion. The device includes a double displacement interferometer, the interferometer of which contains an input beam displacing section including a plurality of orthogonally oriented optical beam displacing elements; a wavelength conversion section including a plurality of orthogonally oriented non-linear optical wavelength converters; an output beam recombination section including a plurality of orthogonally oriented optical beam displacing elements.

Abstract: This disclosure is directed at a method and device capable of producing polarization entangled photon pairs and accomplishing polarization insensitive wavelength conversion. The device includes a double displacement interferometer, the interferometer of which contains an input beam displacing section including a plurality of orthogonally oriented optical beam displacing elements; a wavelength conversion section including a plurality of orthogonally oriented non-linear optical wavelength converters; an output beam recombination section including a plurality of orthogonally oriented optical beam displacing elements.

Abstract: The operating elements for adjusting the tilt of the back rest of the rear seat of a motor vehicle shall be disposed in an area which is easily accessible and permits adjustment of the back rest by the passenger in the sitting position during the ride. This is achieved in that the operating elements of the adjuster are disposed in the area of the opening for the center arm rest that can be folded down from the back rest. It is especially advantageous if the arm rest in the folded-up position conceals the operating elements. It is also possible to integrate the operating elements in the center arm rest and to adjust the tilt of the back rest by moving the arm rest up and down.