Fig. 1. Grooved grating microstructure

Fig. 2. Phase modulation spectra of grooved grating microstructure with wavelengths of (a) 4.8 μm and (b) 10.6 μm

Fig. 3. Transmittance spectra of grooved grating microstructure with wavelengths of (a) 4.8 μm and (b) 10.6 μm

Fig. 4. Distribution of phase retardation

Fig. 5. Distribution of output light field

Fig. 6. Chromatic aberration curves of ZnSe lens (a) without and (b) with grooved grating microstructure

Fig. 7. Coating properties of ZEP520 photoresist

Fig. 8. Testing and stitching of sub-field. (a) Home field offset of 1 mm×1 mm; (b) home field offset of 200 μm×200 μm

Fig. 9. Comparison for graphic quality at different exposure parameters. (a) Insufficient exposure; (b) sufficient exposure

Fig. 10. Surface morphology of sample from SEM

Fig. 11. Measured height of grooved grating microstructure

Fig. 12. Infrared spectroscopy performance with wavelengths of (a) 4.8 μm and (b) 10.6 μm