Fig. 1. Relationship between diffraction efficiency of gold-coated grating and groove depth for TM mode

Fig. 2. Relationship between diffraction efficiency of gold-coated grating and groove depth for TE mode

Fig. 3. Direct laser writing system with a Dammann grating

Fig. 4. Gold-coated grating prepared by our research group

Fig. 5. Schematic of measuring device for TM mode

Fig. 6. Diffraction efficiency map for TM mode. (a) Distribution of measurement points; (b) areal map

Fig. 7. Diffraction efficiency map for TE mode. (a) Distribution of measurement points; (b) areal map