We are developing a highly miniaturized trapped ion clock to probe the 12.6 GHz hyperfine transition in the
171Yb+ ion. The clock development is being funded by the Integrated Micro Primary Atomic Clock
Technology (IMPACT) program from DARPA where the stated goals are to develop a clock that consumes
50 mW of power, has a size of 5 cm3, and has a long-term frequency stability of 10-14 at one month. One of
the significant challenges will be to develop miniature single-frequency lasers at 369 nm and 935 nm and the
optical systems to deliver light to the ions and to collect ion fluorescence on a detector.
This paper describes results from using a microcombustor to create two hydrocarbon gas sensors: one utilizing calorimetry and the other a flame ionization detector (FID) mechanism. The microcombustor consists of a catalytic film deposited on the surface of a microhotplate. This micromachined design has low heat capacity and thermal conductivity, making it ideal for heating catalysts placed on its surface. The catalytic materials provide a natural surface-based method for flame ignition and stabilization and are deposited using a micropen system, which allows precise and repeatable placement of the materials. The catalytic nature of the microcombustor design expands the limits of flammability (LoF) as compared with conventional diffusion flames; an unoptimized LoF of 1-32% for natural gas in air was demonstrated with the microcombustor, whereas conventionally 4-16% is observed. The LoF for hydrogen, methane, propane and ethane are likewise expanded. Expanded LoF permit the use of this technology in applications needing reduced temperatures, lean fuel/air mixes, or low gas flows. By coupling electrodes and an electrometer circuit with the microcombustor, the first ever demonstration of a microFID utilizing premixed fuel and a catalytically-stabilized flame has been performed; the detection of 1.2-2.9 % of ethane in a hydrogen/air mix is shown.
This paper discusses the fundamental technical challenges and solutions in converting still images from film through the digital domain to video. These include tone scale colorimetry quantization and resolution. The digital signal processing for a particular implementation of a slide-to-video transfer unit which employs a single CCD sensor is described. 2.