Optical parametric oscillator

Abstract

The invention relates to a doubly resonant optical parametric oscillator (1) comprising a fan-out crystal (5, 55, 105) having an optical non-linearity of order 2 and placed in an optical cavity (6) able to reflect a pump (2), said crystal (5, 55, 105) comprising an entrance face (59) and an exit face (60), through which faces the optical axis passes, an upper face (57) and a lower face (58). The main feature of an optical parametric oscillator (1) according to the invention is that said crystal (105) includes a grating of polarity-inverted lines (106) originating separately and in a narrowly spaced manner at a fictional upper line (61) that is parallel to the upper face (57) of the crystal (105), and ending separately and in a widely spaced manner either at a fictional lower line (63) that is parallel to the lower face (58) of the crystal (105), or at the entrance face (59) of the crystal, two successive lines (106) making between each other a constant angle, said grating starting with a first line (108) originating at the exit face (60) of the crystal (105) and extending towards the lower fictional straight line (63) while diverging from said exit face (60), all the other lines gradually and monotonically inclining from said first straight line (108) towards the entrance face (59) of the crystal (105).

Dependencies are inferred from the claim text.