Samurai Scientists' members have worked with sensors across the electromagnetic spectrum. We have specific experience in EUV-NUV, visible, MWIR, LWIR, MMW, and radar for imaging and target detection; nonimaging NIR, EM, and UT sensors; and a wide variety of sensor testing methods. We have developed sensors, sensor test systems, and related components (such as projection screens) for government and commercial customers. Our publically-available publications in this area include:

1. Jannson, T.P.; Shnitser, P.I.; Kostrzewski, A.A., et al. “HWIL LIDAR Imaging Sensor, 3-D Synthetic and Natural Environment, and Temporal ATR.” In: Murrer Jr., R.L., editor. Technologies for Synthetic Environments: Hardware-in-the-Loop Testing VII. Orlando, Florida: SPIE; 4717, 2002. p. 68-76. doi:10.1117/12.474708.
         In this paper, LIDAR imaging sensors, 3-D synthetic and natural object-centric environment, and temporal (progressive) ATR (Automatic Target Recognition), are discussed in the context of Modeling and Simulation (M&S) and Hardware-in-theloop HWIL) testing.
2. Kurtz, R.M.; Parfenov, A.V.; Pradhan, R.D., et al. “A New Approach to Wideband Scene Projection.” Multisensor, Multisource Information Fusion: Architectures, Algorithms, and Applications 2005. Orlando, Florida: SPIE; 5813, 2005. p. 312-320.
        Advances in the development of imaging sensors depend upon (among other things) the testing capabilities of research laboratories.  Sensors and sensor suites need to be rigorously tested under laboratory and field conditions before being put to use.  Real-time dynamic simulation of real targets is a key component of such testing, as actual full-scale tests with real targets are extremely expensive and time consuming and are not suitable for early stages of development.  Dynamic projectors simulate tactical images and scenes.  Several technologies exist for projecting IR and visible scenes to simulate tactical battlefield patterns – large format resistor arrays, liquid crystal light valves, Eidophor type projecting systems, and micromirror arrays, for example.  These technologies are slow, or are restricted either in the modulator array size or in spectral bandwidth.  In addition, many operate only in specific bandwidth regions.  Physical Optics Corporation is developing an alternative to current scene projectors.  This projector is designed to operate over the visible, near-IR, MWIR, and LWIR spectra simultaneously, from 300 nm to 20 µm.  The resolution is 2 megapixels, and the designed frame rate is 120 Hz (40 Hz in color).  To ensure high-resolution visible imagery and pixel-to-pixel apparent temperature difference of 100°C, the contrast between adjacent pixels is >100:1 in the visible to near-IR, MWIR, and LWIR.  This scene projector is designed to produce a flickerless analog signal, suitable for staring and scanning arrays, and to be capable of operation in a hardware-in-the-loop test system.  Tests performed on an initial prototype demonstrated contrast of 250:1 in the visible with non-optimized hardware.
3. Yang, Y.; Pradhan, R.D.; Kurtz, R.M., et al. “Portable LIBS and Raman Spectroscopy Standoff Chemical Analysis System.” Presented at Detection and Remediation Technologies for Mines and Minelike Targets XII. SPIE; Orlando, Florida: 2007.
        
4. Swimm, R.T.; Bass, M.; Fathe, L., et al. “Spot Size Dependent Laser Materials Interactions Due to Surface Electromagnetic Waves.” Laser Induced Damage in Optical Materials. Boulder, Colorado: NIST, 1986.
         Measurements of the transient reflectivity change due to heating by a surface electromagnetic wave are reported. Initial results are inconclusive with regard to the existence of surface electromagnetic waves. Implications concerning the effects upon the laser-induced damage threshold are discussed.
5. Kurtz, R.M.; Forrester, T.C. “Optimizing Reception Bandwidth of a Pulsed Signal.” In: Molebny, V., editor. Laser Radar Technologies and Applications XXV. Online Only, California: SPIE; 11410, 2020. p. 114100B. doi:10.1117/12.2558339.
        In a wide variety of applications, including free-space communications, target illumination, and radar (laser, microwave, millimeter wave, etc.), an electromagnetic pulse is collected by a receiver and converted to an electronic signal. This electronic pulse is then amplified before it is processed into digital data, tracking information, or range and velocity values. In this paper it is shown that an optimum amplification half-power bandwidth—in terms of maximum signal-to-noise ratio (SNR)—can be determined, based almost exclusively on the full width at half maximum (FWHM) of the pulse and the roll-off rate of the amplifier at frequencies above the high-frequency cutoff. The shape of the pulse and the specific amplification filter (e.g. Butterworth, Chebyshev, Elliptic, etc.) has little effect on the optimum bandwidth. For example, if the amplifier includes a low-pass first-order Butterworth filter whose half-power frequency is Δν, a pulse whose FWHM is Δt will be amplified at the maximum possible SNR if Δν = 0.146/Δt. This assumes that any noise in the system is essentially white, in that the total noise is proportional to the square root of the amplification bandwidth. It should be noted, and is discussed in this paper, that the maximum SNR may not lead to the ideal bandwidth, since it with distort the shape of the input pulse. This distortion alters the shape of the pulse and may affect the calculation of the pulse centroid, which is particularly important in range and velocity calculations. This may lead to an increase in the optimum bandwidth.
6. Ai, J.; Dimov, F.; Kurtz, R.M.; Gorce, E.J., inventors; Luminit, LLC assignee. Compound Eye Laser Illumination Seeker. Patent US010890417B2. 2021 Jan 12 (Continuation of US010281551B2).
         The Compound Eye Laser Illumination Seeker (CELIS) is a tracking system used to guide items to point at a laser-illuminated target, with the Illumination being either pulsed or modulated at either a specific rate or within a range of rates. The CELIS, comprising a multiaperture compound receiver optics (MACRO) to collect the signal, a set of light guides to combine the received light into light representing individual angular sectors and redirect it to detectors whose output represents the illumination signal in that quadrant, a spectral filter, an angle filter, the set of detectors, and processing electronics. The output is an electronic signal indicating the angular difference between the pointing direction of the signal and the pointing direction of the tracking device.
7. Ai, J.; Dimov, F.; Kurtz, R., inventors; Luminit, LLC assignee. Compound Eye Laser Tracking Device. Patent US010281551B2. 2019 May 9.
         The Compound Eye Laser Illumination Seeker (CELIS) is a tracking system used to guide items to point at a laser-illuminated target, with the Illumination being either pulsed or modulated at either a specific rate or within a range of rates. The CELIS, comprising a multiaperture compound receiver optics (MACRO) to collect the signal, a set of light guides to combine the received light into light representing individual angular sectors and redirect it to detectors whose output represents the illumination signal in that quadrant, a spectral filter, an angle filter, the set of detectors, and processing electronics. The output is an electronic signal indicating the angular difference between the pointing direction of the signal and the pointing direction of the tracking device.