To achieve such a small size required the combination of Hamamatsu’s MEMS and image sensor technologies. The new device uses an aberration-corrected concave grating with a very short focal length, and a blazed grating profile for high diffraction efficiency. The grating is replicated onto the top of a convex glass lens using nano-print technology. Directly opposite the grating is placed a dedicated CMOS silicon image sensor with an on-chip slit. This 75 µm x 750 µm slit is formed into the CMOS chip using MEMS technology. The distance between the sensor and slit is only 1 mm, whilst the grating to image sensor distance a mere 8.5 mm.
Through the use of these novel techniques, the C10988MA can offer a spectral resolution of 12 nm in the wavelength range of 340 nm to 750 nm, making it ideal for a range of visible light applications requiring a miniaturised spectrometer head. This is Hamamatsu working at the forefront of today’s MOEMS technologies, to bring unique and exciting products to an ever demanding market.