ElectroOptical Innovationshttps://electrooptical.net/News/2022-01-20T01:35:07.861794+00:00InGaAs Photodiode Characterization Drift and 1/f Noise at 70-90 °C2017-09-07T16:47:58+00:002017-09-07T20:48:09.866405+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/ingaas-photodiode-characterization-drift-and-1f-noise-at-70-90-c/<p>Drift and 1/f Noise at 70-90 °C<br/>Sometimes you have to find out things that aren't in the datasheet, and even the manufacturer may not know.</p>Thermoacoustic Refrigeration2017-09-07T16:47:30+00:002022-01-20T00:13:24.044214+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/thermoacoustic-refrigeration/<p>Thermoacoustic fridges are magic: you heat one end, and the other end gets cold. (Of course you have to sink all that heat from the middle.) They can easily be made long and skinny, and so are a natural for use down drillholes. They're also made entirely of metal, and have no moving parts, so they will survive bouncing around in the back of a truck.</p>
<p><br/>This was a design study for a general purpose fridge for 2-inch cased holes (38 mm maximum OD) that would solve many of the temperature problems of downhole operation for a wide variety of sensors.</p>Surface Plasmon Resonance Spectrometer2017-09-07T16:47:13+00:002017-09-07T20:47:17.352399+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/surface-plasmon-resonance-spectrometer/<p>Use of my laser noise canceller to achieve shot-noise limited performance in SPR spectroscopy (in cooperation with Xi Wang and Andre Knoesen of UC Davis, and a bunch of my friends at IBM Almaden Research Center).</p>Transdermal glucose detectors based on optical coherence tomography2017-09-07T16:46:56+00:002017-09-07T20:47:00.427366+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/transdermal-glucose-detectors-based-on-optical-coherence-tomography/<p>This was a photon budget for an OCT system—interesting primarily for the effect of path delay in turning FM noise in the superluminescent diode (SLD) into AM noise in the measurement.</p>High resolution touchscreens2017-09-07T16:46:24+00:002017-09-07T20:46:42.351136+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/high-resolution-touchscreens/<p>This was for a midsize start-up making very large, high resolution touchscreen displays—they needed an outside pair of eyes to do some sanity checking of a couple of their proposed designs.</p>Mixed-reality head-mounted projection displays2017-09-07T16:46:01+00:002017-09-07T20:46:09.733815+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/mixed-reality-head-mounted-projection-displays/<p>I chaired a series of formal design reviews for a start-up company making immersive displays with resolution better than the human eye.</p>All-Optical Downlink for Antisubmarine Warfare (ASW) sonobuoys2017-09-07T16:45:42+00:002017-09-07T20:45:52.308614+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/all-optical-downlink-for-antisubmarine-warfare-asw-sonobuoys/<p>Another Della project for the Navy: I did a photon budget that showed that this could be done optically within the power and weight constraints, and would work in bright sun as well as at night. (Optical communications are much harder to intercept or to jam than radio.)</p>Integrating vs. TIA front ends for compressive-scan cameras2017-09-07T16:45:17+00:002022-01-20T01:01:00.002652+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/integrating-vs-tia-front-ends-for-compressive-scan-cameras/<p>A shootout between the two major classes of transimpedance amplifier (TIA) designs for one difficult corner of the design space.</p>13.5 nm EUV Lithography: Tin Droplet Detection System2017-09-07T16:44:13+00:002022-01-20T01:35:07.861794+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/135-nm-euv-lithography-tin-droplet-detection-system/<p>When you're hitting a droplet with enough pulsed CO<sub>2</sub> light to generate X-rays efficiently, you have to know exactly when it's going to cross the focus.</p>RF Design for Ion Trap Mass Spectrometer RGA2017-09-07T16:43:50+00:002017-09-07T20:43:57.729895+00:00Simon Hobbshttps://electrooptical.net/News/author/simon/https://electrooptical.net/News/rf-design-for-ion-trap-mass-spectrometer-rga/<p>Producing an integrated model of circuit conditions and ion motion, allowing optimization of circuit and excitation parameters, plus sanity checking</p>