New Convex Grating Types Manufactured by Electron Beam Lithography

The advantages of spectrometer forms utilizing concentric surfaces have been recognized for some time.1,2 In order to realize these advantages in practice, a reliable and flexible method of generating gratings on curved substrates is needed. Concave gratings are commonly manufactured using both ruling and holographic techniques. However, it is difficult to produce well-blazed curved gratings.3,4,5 These difficulties are exacerbated in concentric spectrometer designs in which the grating must typically cover an arc that is greater than the blaze angle itself.