Methods and apparatus for true high dynamic range imaging

    公开(公告)号:US10694122B2

    公开(公告)日:2020-06-23

    申请号:US16103366

    申请日:2018-08-14

    摘要: When imaging bright objects, a conventional detector array can saturate, making it difficult to produce an image with a dynamic range that equals the scene's dynamic range. Conversely, a digital focal plane array (DFPA) with one or more m-bit counters can produce an image whose dynamic range is greater than the native dynamic range. In one example, the DFPA acquires a first image over a relatively brief integration period at a relatively low gain setting. The DFPA then acquires a second image over longer integration period and/or a higher gain setting. During this second integration period, counters may roll over, possibly several times, to capture a residue modulus 2m of the number of counts (as opposed to the actual number of counts). A processor in or coupled to the DFPA generates a high-dynamic range image based on the first image and the residues modulus 2m.

    Methods and apparatus for true high dynamic range imaging

    公开(公告)号:US11632507B2

    公开(公告)日:2023-04-18

    申请号:US17577867

    申请日:2022-01-18

    摘要: When imaging bright objects, a conventional detector array can saturate, making it difficult to produce an image with a dynamic range that equals the scene's dynamic range. Conversely, a digital focal plane array (DFPA) with one or more m-bit counters can produce an image whose dynamic range is greater than the native dynamic range. In one example, the DFPA acquires a first image over a relatively brief integration period at a relatively low gain setting. The DFPA then acquires a second image over longer integration period and/or a higher gain setting. During this second integration period, counters may roll over, possibly several times, to capture a residue modulus 2m of the number of counts (as opposed to the actual number of counts). A processor in or coupled to the DFPA generates a high-dynamic range image based on the first image and the residues modulus 2m.

    METHODS AND APPARATUS FOR TRUE HIGH DYNAMIC RANGE (THDR) TIME-DELAY-AND-INTEGRATE (TDI) IMAGING

    公开(公告)号:US20190124279A1

    公开(公告)日:2019-04-25

    申请号:US16163910

    申请日:2018-10-18

    摘要: In time-delay-and-integrate (TDI) imaging, a charge-couple device (CCD) integrates and transfers charge across its columns. Unfortunately, the limited well depth of the CCD limits the dynamic range of the resulting image. Fortunately, TDI imaging can be implemented with a digital focal plane array (DFPA) that includes a detector, analog-to-digital converter (ADC), and counter in each pixel and transfer circuitry connected adjacent pixels. During each integration period in the TDI scan, each detector in the DFPA generates a photocurrent that the corresponding ADC turns into digital pulses, which the corresponding counter counts. Between integration periods, the DFPA transfers the counts from one column to the next, just like in a TDI CCD. The DFPA also non-destructively transfers some or all of the counts to a separate memory. A processor uses these counts to estimate photon flux and correct any rollovers caused by “saturation” of the counters.

    Methods and apparatus for true high dynamic range imaging

    公开(公告)号:US11252351B2

    公开(公告)日:2022-02-15

    申请号:US16897339

    申请日:2020-06-10

    摘要: When imaging bright objects, a conventional detector array can saturate, making it difficult to produce an image with a dynamic range that equals the scene's dynamic range. Conversely, a digital focal plane array (DFPA) with one or more m-bit counters can produce an image whose dynamic range is greater than the native dynamic range. In one example, the DFPA acquires a first image over a relatively brief integration period at a relatively low gain setting. The DFPA then acquires a second image over longer integration period and/or a higher gain setting. During this second integration period, counters may roll over, possibly several times, to capture a residue modulus 2m of the number of counts (as opposed to the actual number of counts). A processor in or coupled to the DFPA generates a high-dynamic range image based on the first image and the residues modulus 2m.