| 摘要 |
<p>Methods and systems for carrying out the distribution of light in a ray pathway (21) into wavelength components (21 - 27) comprising optical elements (10, 11) of the diffraction grating type that diffract the said light into several spectral orders (m). The invention is characterised in that at least two diffraction grating surfaces are placed sequentially in the ray pathway whose orientations and grating constants are selected such that the wavelength components that are diffracted at the grating surfaces into the respective orders, whose sum (M = m1 + m2) is constant, emerge from the last grating surface (11) in essentially the same direction.</p> |
