Hamamatsu Photonics has introduced the C10988MA, an ultra-compact spectrometer built using MOEMS technology. The C10988MA is a thumb-sized device, measuring only 27.6 x 13 x 16.8mm, developed for use in portable and hand-held devices, where a standard mini-spectrometer would be too large and consume too much power. The C10988MA is also light, weighing only 9g.
To achieve such a small size required the combination of Hamamatsu's MEMS and image sensor technologies. The 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 x 750µm slit is formed into the CMOS chip using MEMS technology. The distance between the sensor and slit is only 1mm, while the grating to image sensor distance 8.5mm.
Through the use of these novel techniques, the C10988MA can offer a spectral resolution of 12nm in the wavelength range of 340nm to 750nm, making it ideal for a range of visible light applications requiring a miniaturised spectrometer head.