I looked into line cameras for a project. I think their main application is in quality control of food on conveyer belts. There are plenty of automated sorting systems that can become a bottleneck. One of the units I speced out could record an 8k pixel line at up to 40kfps.

https://youtu.be/E_I9kxHEYYM

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SJC_Hacker 4 days ago | parent | next [-]

They are used in OCT (optical coherence tomography) as well

OCT is a technique which uses IR to get "through" tissue using beam in the near infrared (roughly 950 nm, with a spread of roughly 100 nm). The return is passed through interferometer and what amounts to a diffraction grating to produce the "spread" that the line camera sees. After some signal processing (FFT is a big one), you can get the intensity at depth. If you sweep in X,Y somehow, usually deflecting the beam with a mirror, you can obtain a volumetric image like an MRI or sonogram. Very useful for imaging the eye, particularly the back of the retina where the blood vessels are.

	▲	s0rce 4 days ago \| parent [-]
		Yah, lots of neat line scan camera applications in spectroscopy. Basically any grating application. 950nm would be on the edge of where you'd implement a Si CCD for OCT as the sensitivity drops as the Si is no longer absorbing. InGaAs detectors are used further in the NIR.

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tcpekin 4 days ago | parent | prev [-]

Satellites are also a big use case.

	▲	defrost 4 days ago \| parent [-]
		A number of the sats I worked with are single point cameras .. the satellite spins about a major axis orientated in the direction of travel, the point camera rotates with the satellite and a series of points of data are written to a line of storage as the camera points at the earth and pans across as the sat also moves forward. Data stops being written as the sat rotates the camera away from the planet and resumes once it has rolled over enough to again point at the earth. It may seem like a pedantic difference; a "line scan camera" is stationary while mirrors inside it spin or another mechanism causes it to "scan" a complete vertical line - perhaps all at once, perhaps as the focal point moves Vs a camera in a satellite that has no moving parts that just records a single point directly in front of the instrument .. and the entire satellite spins and moves forwards.