title: High-efficiency diffractive micromachined chopper for infrared wavelength and its application to a pyroelectric infrared sensor.
abstract: We have developed a diffractive micromachined chopper (DMC) for an IR wavelength of ~10 mum. This device operates mechanically by movable reflection grating beams. It modulates the diffraction efficiency by controlling the displacement of grating beams by an electrostatic force. For a CO(2) laser beam, a high modulation efficiency of 84% with an -0.8-dB small insertion loss was obtained by detecting 0th-order diffracted light. A novel pyroelectric IR microsensor with a DMC and a diffractive multilevel Si microlens was proposed and it demonstrated the detection of human existence.
authors.forename: M
authors.initials: M
authors.lastname: Ueda
authors.forename: T
authors.initials: T
authors.lastname: Shiono
authors.forename: T
authors.initials: T
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Yokoyama