Search NASA⌕ Search

SEARCH · Search NASA

Results for “pixel detector”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16

SCA Test Report: H4RG-21317 WFIRST

This report summarizes the measured performance for the Sensor Chip Assembly (SCA), which is identified in Table 1. The SCA architecture is a substrate-removed HgCdTe detector with an area of 4096x4096 pixels (with a reference pixel area of four pixels deep around all four sides, available to substitute corresponding image pixels) and a pixel pitch of 10 μm.This SCA has been tested at the Goddard Space Flight Center (GSFC/NASA) Detector Characterization Laboratory (DCL). Teledyne (the vendor) classifies its detectors into different grades based on testing performed at its facility. The classification of this SCA and the tested dates are included in Table 1 below. The tests performed on this array are derived from the document WFIRST-PROC-09220_WFIRST-SCA-ATP_-.docx. A summary of the test parameters, requirements, and test results is presented in Table 2. The details of each test are subsequently described in the report. In the Summary (Table 2), SCA results are reported at an operating temperature of 95K, and 1.0 V bias voltage. In the detailed section of each test, the results for 95 K and 0.5V bias voltage is also reported. The data for the result reported in this document was acquired in pixel reset mode. For all cases, the frame time used is 2.830 seconds. Reference pixel correction was applied to every raw frame.

Laddawan Miko↗

SCA Test Report: H4RG-21319 WFIRST

This report summarizes the measured performance for the Sensor Chip Assembly (SCA), which is identified in Table 1. The SCA architecture is a substrate-removed HgCdTe detector with an area of 4096x4096 pixels (with a reference pixel area of four pixels deep around all four sides, available to substitute corresponding image pixels) and a pixel pitch of 10 µm. This SCA has been tested at the Goddard Space Flight Center (GSFC/NASA) Detector Characterization Laboratory (DCL). Teledyne (the vendor) classifies its detectors into different grades based on testing performed at its facility. The classification of this SCA and the tested dates are included in Table 1 below. The tests performed on this array are derived from the document WFIRST-PROC-09220_WFIRST-SCA-ATP_-.docx. A summary of the test parameters, requirements, and test results is presented in Table 2. The details of each test are subsequently described in the report. In the Summary (Table 2), SCA results are reported at an operating temperature of 95K, and 1.0 V bias voltage. In the detailed section of each test, the results for 95 K and 0.5V bias voltage is also reported. The data for the result reported in this document was acquired in pixel reset mode. For all cases, the frame time used is 2.830 seconds. Reference pixel correction was applied to every raw frame.

Laddawan Miko↗

SCA Test Report H4RG-21813: Roman Space Telescope

This report summarizes the measured performance for the Sensor Chip Assembly (SCA), which is identified in Table 1. The SCA architecture is a substrate-removed HgCdTe detector with an area of 4096x4096 pixels (with a reference pixel area of four pixels deep around all four sides, available to substitute corresponding image pixels) and a pixel pitch of 10 μm.This SCA has been tested at the Goddard Space Flight Center (GSFC/NASA) Detector Characterization Laboratory (DCL). Teledyne (the vendor) classifies its detectors into different grades based on testing performed at its facility. The classification of this SCA and the tested dates are included in Table 1 below. The tests performed on this array are derived from the document WFIRST-P ROC-09220_WFIRST-SCA-ATP_-.docx.A summary of the test parameters, requirements, and test results is presented in Table 2. The details of each test are subsequently described in the report. In the Summary ( Table 2), SCA results are reported at an operating temperature of 95K, and 1.0 V bias voltage. In the detailed section of each test, the results for 95 K and 0.5V bias voltage is also reported. The data for the result reported in this document was acquired in pixel reset mode. For all cases, the frame time used is 2.830 seconds. Reference pixel correction was applied to every raw frame.

Laddawan Miko↗

SCA Test Report H4RG-21814: Roman Space Telescope

This report summarizes the measured performance for the Sensor Chip Assembly (SCA), which is identified in Table 1. The SCA architecture is a substrate-removed HgCdTe detector with an area of 4096x4096 pixels (with a reference pixel area of four pixels deep around all four sides, available to substitute corresponding image pixels) and a pixel pitch of 10 μm.This SCA has been tested at the Goddard Space Flight Center (GSFC/NASA) Detector Characterization Laboratory (DCL). Teledyne (the vendor) classifies its detectors into different grades based on testing performed at its facility. The classification of this SCA and the tested dates are included in Table 1 below. The tests performed on this array are derived from the document WFIRST-P ROC-09220_WFIRST-SCA-ATP_-.docx.A summary of the test parameters, requirements, and test results is presented in Table 2. The details of each test are subsequently described in the report. In the Summary ( Table 2), SCA results are reported at an operating temperature of 95K, and 1.0 V bias voltage. In the detailed section of each test, the results for 95 K and 0.5V bias voltage is also reported. The data for the result reported in this document was acquired in pixel reset mode. For all cases, the frame time used is 2.830 seconds. Reference pixel correction was applied to every raw frame.

Laddawan Miko↗

SCA Test Report: H4RG-20833 WFIRST

This report summarizes the measured performance for the Sensor Chip Assembly (SCA), which is identified in Table 1. The SCA architecture is a substrate-removed HgCdTe detector with an area of 4096x4096 pixels (with a reference pixel area of four pixels deep around all four sides, available to substitute corresponding image pixels) and a pixel pitch of 10 μm. This SCA has been tested at the Goddard Space Flight Center (GSFC/NASA) Detector Characterization Laboratory (DCL). Teledyne (the vendor) classifies its detectors into different grades based on testing performed at its facility. The classification of this SCA and the tested dates are included in Table 1 below.The tests performed on this array are derived from the document WFIRST-PROC-09220_WFIRST-SCA-ATP_-.docx. A summary of the test parameters, requirements, and test results is presented in Table 2. The details of each test are subsequently described in the report. In the Summary (Table 2), SCA results are reported at an operating temperature of 95K, and 1.0 V bias voltage. In the detailed section of each test, the results for 90 K (1.0V bias voltage) and 95 K (0.5V bias voltage) are also reported. For all cases, the frame time used is 2.764 seconds. Reference pixel correction was applied to every raw frame.

Laddawan Miko↗

Sensor Chip Assembly (SCA) Test Report

This report summarizes the measured performance for the Sensor Chip Assembly (SCA), which is identified in Table 1. The SCA architecture is a substrate-removed HgCdTe detector with an area of 4096x4096 pixels (with a reference pixel area of four pixels deep around all four sides, available to substitute corresponding image pixels) and a pixel pitch of 10 μm. This SCA has been tested at the Goddard Space Flight Center (GSFC/NASA) Detector Characterization Laboratory (DCL). Teledyne (the vendor) classifies its detectors into different grades based on testing performed at its facility. The classification of this SCA and the tested dates are included in Table 1 below. The tests performed on this array are derived from the document WFIRST-PROC-09220_WFIRST-SCA-ATP_-.docx. A summary of the test parameters, requirements, and test results is presented in Table 2. The details of each test are subsequently described in the report. In the Summary (Table 2), SCA results are reported at an operating temperature of 95K, and 1.0 V bias voltage. In the detailed section of each test, the results for 90 K (1.0V bias voltage) and 95 K (0.5V bias voltage) are also reported. For all cases, the frame time used is 2.764 seconds. Reference pixel correction was applied to every raw frame.

WFIRST SCA TEST REPORT↗

SCA Test Report, H4RG-20829 WFIRST

This report summarizes the measured performance for the Sensor Chip Assembly (SCA), which is identified in Table 1. The SCA architecture is a substrate-removed HgCdTe detector with an area of 4096x4096 pixels (with a reference pixel area of four pixels deep around all four sides, available to substitute corresponding image pixels) and a pixel pitch of 10 μm. This SCA has been tested at the Goddard Space Flight Center (GSFC/NASA) Detector Characterization Laboratory (DCL). Teledyne (the vendor) classifies its detectors into different grades based on testing performed at its facility. The classification of this SCA and the tested dates are included in Table 1 below. The tests performed on this array are derived from the document WFIRST-PROC-09220_WFIRST-SCA-ATP_-.docx. A summary of the test parameters, requirements, and test results is presented in Table 2. The details of each test are subsequently described in the report. In the Summary (Table 2), SCA results are reported at an operating temperature of 95K, and 1.0 V bias voltage. In the detailed section of each test, the results for 90 K (1.0V bias voltage) and 95 K (0.5V bias voltage) are also reported. For all cases, the frame time used is 2.764 seconds. Reference pixel correction was applied to every raw frame.

Laddawan R Miko↗

Characterization of EJ-270 and Ce-doped LiCAF scintillators for the development of high-rate neutron reflectometer detectors

The Second Target Station of the Spallation Neutron Source at Oak Ridge National Laboratory is anticipated to provide a neutron source with ∼20 times increase in peak brightness than the First Target Station. The neutron reflectometers currently in operation at the First Target Station need to be upgraded due to the increased neutron flux. A prototype neutron detector module based upon a pixelated scintillator array readout by silicon photomultipliers is being developed to address the high-rate challenge faced with future neutron reflectometer instruments at the Second Target Station. Two types of scintillator materials were considered for this detector development, i.e., 6 Li-loaded EJ-270 plastic scintillator and Ce-doped LiCAF single crystal. This paper reports the scintillator characterization results, including light yield, pulse shape discrimination performance, capability to detect thermal neutrons in a high γ-ray field, and γ-ray sensitivity. The number of photons produced per neutron capture by EJ-270 and LiCAF:Ce was measured to be 2176 ± 91 and 2651 ± 108, respectively. EJ-270 demonstrated a good capability to discriminate between neutrons and γ-rays by employing the commonly used charge comparison method (figure-of-merit: 1.13 ± 0.01 for an energy cut of 292–426 keVee) and a reasonable performance when using the time-over-threshold techniques; however, no discrimination was observed from LiCAF:Ce regardless of the pulse shape discrimination approaches utilized, making pulse height discrimination necessary for LiCAF:Ce to differentiate between neutrons and γ-rays. Both EJ-270 and LiCAF:Ce exhibited an acceptable capacity to detect thermal neutrons at high exposure rates up to approximately 584 mR/h. Furthermore, the γ-ray sensitivities measured with a 60 Co source at an exposure rate of around 1145 mR/h were determined to be (6.11 ± 0.87) × 10 −6 and (7.64 ± 1.08) × 10 −7 for EJ-270 and LiCAF:Ce, respectively.

EJ-270↗

Infrared astronomical imaging using a microcomputer data system

A small, portable data-acquisition and display system with a unique coprocessor was designed and built to collect data from infrared array detectors for astronomical and laboratory use. The system consists of a microcomputer board, two 12-bit analog-to-digital data-acquisition boards, a color-graphics driver board, and two coprocessor boards. The coprocessors are arithmetic logic units designed to achieve the high computation rates necessary for real-time infrared background cancellation. The system can collect data from infrared detectors of 1 to 256 pixel elements with a computation rate of 768 kHz. The software for the system was designed to collect data in the system's background, while performing other tasks in the system's foreground. The data for the detector arrays is stored in block fashion to facilitate variable image size.

Stafford, P. S.↗

Testing and characterization of an IR CBIRD FPA

High performance IR cameras are in great demand for a variety of applications, including defense (e.g. night vision, missile detection) and space (e.g. imaging at IR wavelengths). IR focal plane arrays (FPAs) are an essential component of IR cameras. An FPA is a collection of detectors at the focal plane of an imaging device, where each detector can be thought of a pixel in the image it is detecting. The FPA in this study is based on Complimentary Barrier Infrared Detectors (CBIRDs). The CBIRD FPA was tested by imaging flat black body targets at three different temperatures, 20ºC, 25ºC, and 30ºC, with images captured using SEIR software. The important figures of merit for an IR FPA, Noise Equivalent Difference Temperature (NEDT), Noise Equivalent Irradiance (NEI), detectivity (D*), responsivity, and quantum Efficiency (QE), were extracted from the image data for each individual detector using a MATLAB program, as was the array Modulation Transfer Function MTF. The test results show a mean NEDT of 16.98mK and an MTF of about 0.34 at the Nyquist frequency. Overall, the array performs well in the MWIR range and takes quality IR images.

Das, Tanya↗

Modeling and Measuring Charge-Sharing in Hard X-ray Imagers Using HEXITEC CdTe Detectors

The Rutherford Appleton Laboratory's HEXITEC ASIC has been designed to provide fine pixelated X-ray spectroscopic imaging in combination with a CdTe or CZT detector layer. Although HEXITEC's small pixels enable higher spatial resolution as well as higher spectral resolution via the small-pixel effect, they also increase the probability of charge sharing, a process which degrades spectral performance by dividing the charge induced by a single photon among multiple pixels. In this paper, we investigate the effect of this process on a continuum X-ray spectrum below the Cd and Te fluorescence energies (23 keV). This is done by comparing laboratory measurements with simulations performed with a custom designed model of the HEXITEC ASIC. We find that the simulations closely match the observations implying that we have an adequate understanding of both charge sharing and the HEXITEC ASIC itself. These results can be used to predict the distortion of a spectrum measured with HEXITEC and will help determine to what extent it can be corrected. They also show that models like this one are important tools in developing and interpreting observations from ASICs like HEXITEC.

Ryan, Daniel F.↗

Speckle spectroscopy; an application for the multi-anode microchannel array detector system

Plans to combine the High Angular Resolution Imager/Spectrometer on the 4-meter Mayall telescope at the Kitt Peak National Observatory and the (256 x 1024)-pixel Multi-Anode Microchannel Array detector system to produce a unique instrument for speckle spectroscopy are described. The pulse-counting detector system will provide distortion-free imaging and will time tag each spatially-resolved photon event with an accuracy of 100 ns. The Imager/Spectrometer will provide a spatial resolution of 0.07 arcsec orthogonal to the plane of dispersion and 0.18 arcsec in the plane of dispersion.

Butcher, H. R.↗

In-Flight Performance of the Soft X-Ray Spectrometer Detector System on ASTRO-H

The SXS instrument was launched aboard the Astro-H observatory on February 17, 2016. The SXS spectrometer is based on a high sensitivity x-ray calorimeter detector system that has been successfully deployed in many ground and sub-orbital spectrometers. The instrument was to provide essential diagnostics for nearly every class of x-ray emitting objects from the atmosphere of Jupiter to the outskirts of galaxy clusters, without degradation for spatially extended objects. The SXS detector system consisted of a 36-pixel cryogenic microcalorimeter array operated at a heat sink temperature of 50 mK. In pre-flight testing, the detector system demonstrated a resolving power of better than 1300 at 6 keV with a simultaneous band-pass from below 0.3 keV to above 12 keV with a timing precision better than 100 microsecond. In addition, a solid-state anti-coincidence detector was placed directly behind the detector array for background suppression. The detector error budget included the measured interference from the SXS cooling system and the spacecraft. Additional margin for on-orbit gain-stability, and on-orbit spacecraft interference were also included predicting an on-orbit performance that meets or exceeds the 7 eV FWHM at 6 keV requirement. The actual on-orbit spectral resolution was better than 5 eV FWHM at 6 keV, easily satisfying the instrument requirement. Here we discuss the actual on-orbit performance of the SXS detector system and compare this to performance in pre-flight testing and the on-orbit predictions. We will also discuss the on-orbit gain stability, additional on-orbit interference, and measurements of the on-orbit background.

X-ray astrophysics↗

Far-infrared Imager and Polarimeter for the Origins Space Telescope

The far-infrared imager and polarimeter (FIP) for the Origins Space Telescope (Origins) is a basic far-infrared imager and polarimeter. The camera will deliver continuum images and polarization measurements at 50 and 250μm. Currently available detector technologies provide sufficient sensitivity for background limited observations from space, at least on a single pixel basis. FIP incorporates large next-generation superconducting detector arrays and our technology development plan will push the pixel numbers for the arrays to the required size of 8000. Two superconducting detector technologies are currently candidates for the instrument: transition edge sensors or microwave kinetic inductance devices. Using these detectors and taking advantage of the cryogenic telescope that is provided by Origins, FIP will achieve mapping speeds of up to eight orders of magnitude faster than what has been achieved by existing observatories. The science drivers for FIP include observations of solar system objects, dust properties, and magnetic field studies of the nearby interstellar medium, and large scale galaxy surveys to better constrain the star formation history of the universe to address one of the main themes of Origins: “How does the Universe work?” In addition to the science, the FIP instrument plays a critical functional role in aligning the mirrors during on orbit observatory commissioning.

Astronomy↗

A 5-18 micron array camera for high-background astronomical imaging

A new infrared array camera system using a Hughes/SBRC 58 x 62 pixel hybrid Si:Ga array detector has been successfully applied to high-background 5-18-micron astronomical imaging observations. The off-axis reflective optical system minimizes thermal background loading and produces diffraction-limited images with negligible spatial distortion. The noise equivalent flux density (NEFD) of the camera at 10 microns on the 3.0-m NASA/Infrared Telescope Facility with broadband interference filters and 0.26 arcsec pixel is NEFD = 0.01 Jy/sq rt min per pixel (1sigma), and it operates at a frame rate of 30 Hz with no compromise in observational efficiency. The electronic and optical design of the camera, its photometric characteristics, examples of observational results, and techniques for successful array imaging in a high- background astronomical application are discussed.

Gezari, Daniel Y.↗

Fabrication of a Hybrid Transition Edge Sensor Array for Lynx

Lynx is a proposed NASA X-Ray telescope flight mission aimed at achieving state-of-the-art angular and energy resolution with a 100 kilopixel array to probe the hot energetic young universe in unprecedented detail. To achieve these goals, our team plans on leveraging our current work in development of the focal plane for the Athena X-Ray Integral Field Unit (X-IFU) while advancing the state-of-the-art in transition edge sensor (TES) X-ray detector technology. The TES is an optimal technology for achieving both high energy and fine angular resolution at the same time because pixel features can be made extremely small and the absorber which dominates the heat capacity can be tuned to meet resolution requirements. Specifically, the proposed mission concept calls for a hybrid detector of three different arrays fabricated in the same planar process in one focal plane and optimized for different science goals. The main arrays consist of 5x5 hydras, 25 pixels of 4 micron thick Au absorbers each with a different thermal link to one common TES. The outer array has absorbers on a 50-micron pitch for most of the 5 arc-minute field-of-view, and the inner array has 25-micron absorbers for the central 1 arc-minute region. A high resolution array consisting of single pixel 1 micron thick Au absorbers on 50-micron pitch will lie off to the side. Reading out an array of this magnitude will likely require improvements in indium bump bonding to superconducting flexible wiring. Fabrication of absorbers of two different sizes requires electroplating through a photoresist mold by careful tuning of the current density to achieve uniform flat absorbers on a fine pitch scale, followed by ion milling to yield narrow streets separating the pixels while preserving high quantum efficiency. We report on progress made at fabricating the hybrid array with different absorber sizes and thicknesses. Further, we also report on ongoing work to adequately heat sink the pixels with backside wire bonding and copper coating. We also report on work to improve detector pixel yield and top side indium bump bonding to flexible wiring.

Focal plane array↗

High-resolution spectroscopy with the multi-anode microchannel array detector systems

The results of a series of high-resolution spectroscopic observations undertaken with a linear (1 x 1024)-pixel visible-light Multi-Anode Microchannel Array (MAMA) detector on the Coudespectrograph of the 2.2-meter telescope at the Mauna Kea Observatory and on the vacuum spectrograph of the McMath Solar telescope at the Kitt Peak National Observatory are described. In addition, the two-dimensional MAMA detector systems with (16 x 1024)-pixel, (24 x 1024)-pixel, and (256 x 1024)-pixel formats which are now being readied for use in a series of ground-based, balloon, and sounding-rocket observing programs are briefly described.

Timothy, J. G.↗

WFC3 Calibration and Data Processing

Wide Field Camera 3 (WFC3), a panchromatic imager being developed for the Hubble Space Telescope (HST), is now fully integrated and over the past year has completed first rounds of extensive ground testing at Goddard Space Flight Center (GSFC), in both ambient and thermal-vacuum test environments. This report summarizes the results of those tests and describes the pipeline processing methods that will be used to calibrate WFC3 data. WFC3 is designed to ensure that the superb imaging performance of HST is maintained through the end of the mission and takes advantage of recent developments in detector technology to provide new and unique capabilities for HST. WFC3 contains ultraviolet/visible (UVIS) and near-infrared (IR) imaging channels, offering high sensitivity and wide field of view over the broadest wavelength range of any HST instrument. It is slated to replace the current Wide Field and Planetary Camera 2 during Servicing Mission 4. The WFC3 UVIS channel is based on elements from the Advanced Camera for Surveys (ACS)Wide Field Camera (WFC), with a 4096x4096 pixel Marconi CCD covering a 160x160 arcsecond field of view. The WFC3 UVIS channel is optimized for maximum sensitivity in the near-UV and contains a complement of 48 spectral filters and a grism. The WFC3 IR channel uses a 1024x1024 pixel HgCdTe Hawaii-1R detector array covering a 135x135 arcsecond field of view. The array sensitivity is optimized in the 0.8-1.7micron spectral range. The IR channel accomodates 15 filters and 2 grisms for slitless spectroscopy.

Bushouse, H.↗