Science Alert February 24, 2023 Ghost imaging involves the exploitation of non-local photon spatial correlations to image objects with light that has not interacted with them and, using intelligent spatial scanning with projective masks, reduces detection to a single pixel. Despite many applications, extension to complex amplitude objects remains challenging. Researchers in South Africa revealed that the necessary interference for phase retrieval was naturally embedded in the correlation measurements formed from traditional projective masks in bi-photon quantum ghost imaging. Using this, they developed a simple approach to obtain the full phase and amplitude information of complex objects. They demonstrated straightforward […]
Tag Archives: Ghost imaging
Lasers and terahertz waves combined in camera that sees ‘unseen’ detail
Science Daily February 18, 2020 The core challenge in THz cameras is not about collecting an image, but preserving the objects spectral fingerprint that can be easily corrupted by the technique. Researchers in the UK used a single-pixel camera to image sample objects with patterns of THz light. The prototype they built can detect how the object alters different patterns of THz light. By combining this information with the shape of each original pattern the camera reveals the image of an object as well as its chemical composition. The camera creates THz electromagnetic waves very close to the sample, similar […]
Researchers capture moving object with ghost imaging
Science Daily November 13, 2019 Ghost imaging has been limited to stationary objects because it takes a long time to project the sequence of light patterns onto the object that is necessary to reconstruct an image making blurry. The ghost imaging technique forms an image by correlating a beam that interacts with the object and a reference beam that does not interact with te object. Individually, the beams don’t carry any meaningful information about the object. To apply ghost imaging to moving objects researchers in China used a small number of light patterns to capture the position and trajectory of […]
Toward Ghost Imaging on a Chip
Optics and Photonics February 12, 2019 To overcome the bulky spatial light modulators and other optical components for ghost imaging, researchers in Japan used a phased array of 128 tiny phase shifters packed onto a chip with a 4×4-mm footprint. In the chip setup, input light from a 1550-nm laser, coupled into the array via a lensed fiber, is split into 128 waveguides and piped into the phase-shifting elements of the array. Each individual phase shifter can be electrically controlled, allowing rapid creation of a series of random speckled patterns at refresh rates faster than the few-frame-per-second. The random pattern […]
Physicists hack the human visual system to create “ghost images”
MIT Technology Review August 31, 2018 Computational ghost imaging technique relies on clever algorithms to crunch the seemingly random data that a single pixel appears to gather. Researchers in the UK have demonstrated that the computational integration can be performed directly with the human eye. They used this human ghost imaging technique to evaluate the temporal response of the eye and establish the image persistence time to be around 20 ms followed by a further 20 ms exponential decay. These persistence times agree with previous studies but can now potentially be extended to include a more precise characterisation of visual […]