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We suggest what we believe is a new three-dimensional (3-D) camera system for integral photography. Our method enables high-resolution 3-D imaging. In contrast to conventional integral photography, a moving microlens array (MLA) and a low-resolution camera are used. The intensity distribution in the MLA image plane is sampled sequentially by use of a pinhole array. The inversion problem from pseudoscopic to orthoscopic images is dealt with by electronic means. The new method is suitable for real-time 3-D imaging. We verified the new method experimentally. Integral photographs with a resolution of 3760 pixels x 2560 pixels (188 x 128 element images) are presented.

We present a new fabrication sequence for integrated-silicon microstructures designed and manufactured in a conventional complentary metal-oxide-semiconductor (CMOS) process. The sequence employs a post-CMOS deep silicon backside etch, which allows fabrication of high aspect ratio (25:1) and flat (greater than 10 mm radius of curvature) MEMS devices with integrated circuitry. A comb-drive resonator, a cantilever beam array and a -axis accelerometer were fabricated using this process sequence. Electrical isolation of single-crystal silicon was realized by using the undercut of the reactive ion etch (RIE) process. Measured out-of-plane curling across a 120m-wide 25-m-thick silicon released plate was 0.15 m, which is about ten times smaller than curl of the identical design as a thin-film CMOS microstructure. The -axis DRIE accelerometer structure is 0.4 mm by 0.5 mm in size and has a 25-m-thick single-crystal silicon proof mass. The measured noise floor is 1 mG/ Hz, limited by electronic noise. A vertical electrostatic spring "hardening" effect was theoretically predicted and experimentally verified.[687] IndexTerms-Complentary metal-oxide-semiconductor (CMOS) MEMS, deep reactive ion etch (DRIE), electrostatic spring, inertial sensors.

Polymer replication technique enables for low cost devices even in the case of aspheric or irregular shaped surfaces, submicron or other challenging structures. The use of UV-reaction moulding on semiconductors, glass or other inorganic substrates as the replication technique leads to a high degree of stability and allows for the simultaneous integration of optoelectronics or ion exchanged GRIN elements. Thin polymer layers on inorganic substrates show high flatness and lower wavefront deviations with respect to all?polymer elements. They show low lateral shrinkage during the UV-polymerisation, and the lateral thermal expansion is determined by the substrate. Furthermore, sensitive substrates can be used because the process does not involve high mechanical stress or elevated temperatures. Original structures for the replication masters are fabricated by different resist technologies. Subsequently, they are proportionally transferred by dry etching (RIE) into glass or silicon, or, the resist structure is transformed into a metal master by electroplating. The utilisation of UV-transparent replication tools allows for the use of opaque substrates (i.e. detectors). Locally UV-transparent replication tools enable a combination of replication and resist technology (leading to elements with new features) or can protect sensitive areas like bond pads from being coated with optical layers. The fabrication of isolated polymer elements on arbitrary substrates is an advantage of UV?reaction moulding against injection moulding or hot embossing

The main challenges of fabricating diffraction gratings for use in earth monitoring spectrometers are given by the requirements for low stray light, high diffraction efficiency and a low polarization sensitivity. Furthermore the use in space also requires a high environmental stability of these gratings.We found that holography in combination with ion beam plasma etching provides a way to obtain monolithic, robust fused silica gratings which are able to meet the above mentioned requirements for space applications. Holography accompanied by plasma etching allows the fabrication of a wide range of different grating profiles to optimize the efficiency including the polarization behavior according to a wealth of applications. Typical profile shapes feasible are blazed gratings, sinusoidal profiles and binary profiles and this allows to tailor the efficiency and polarization requirements exactly to the spectral range of the special application. Holographic gratings can be fabricated on plane and also on curved substrates as core components of imaging spectrometers.In this paper we present our grating fabrication flow for the example of plane blazed gratings and we relate the efficiency and stray light measurement results to certain steps of the process. The holographic setup was optimized to minimize stray light and ghosting recorded by the photoresist during the exposure. Low wave front deviations require the use of highly accurate grating substrates and high precision optics in the holographic exposure.

A replication technique allowing for the wafer scale integration ofmicrooptical elements is presented and illustrated by various examples. The technique is based on polymer UV reaction moulding using a modified contact mask aligner where mask and wafer are replaced by the replication tool and an arbitrary substrate (on top ofwhich the microstructures are to be replicated), respectively. The technology takes advantage ofthe high precision and adjustment accuracy of photolithography equipment. The replication masters are nickel shims, etched Silicon wafers or uv-transparent fused silica tools. The latter ones allow for replication on opaque substrates. Additionally, polymer elements with unique properties can be obtained by the combination ofreplication and resist technology using partially transparent replication tools. Wafer scale hybrid integration of micro-optical subsystems is accomplished by replication of polymer elements like lenses, lens arrays, micro prisms etc. onto semiconductor wafers containing detectors or VCSELs, or, by combining micro-optical elements on both sides of a glass wafer. The use ofthin layers ofuv cured (crosslinked) polymers on inorganic substrates results in good thermal and mechanical stability compared to all-polymer devices.

We present a new fabrication sequence for integrated-silicon microstructures designed and manufactured in a conventional CMOS process. The sequence employs a post-CMOS deep silicon backside etch, which allows fabrication of high aspect ratio (25:1) and flat MEMS devices with integrated circuitry. A comb-drive actuator and a beam resonator were fabricated using this process sequence. Electrical isolation of single-crystal silicon was realized by using the undercut of the reactive ion etch (RIE) process. The fabricated devices were actuated electrostatically and flatness characterized using interferometric measurements.