METHOD OF MAKING AND DIFFRACTION DEVICE FOR IR-RADIATION Russian patent published in 1995 - IPC

FIELD: first order diffraction production. SUBSTANCE: diffraction device has substrate with reflecting surface, onto which one pair of dielectric covering layers is disposed. External layer is made in form of diffraction grating. Grooves of the layer are made through the total depth of the layer. Thickness of the layer is lower than quarter wavelength. Thickness of the other layer of the pair differs from value which is multiple to quarter of the wavelength. EFFECT: improved efficiency. 2 cl, 5 cl, 3 dwg