Single-Pixel Camera Takes 3D Images

Scientists have discovered an affordable way to take 3D images. A Glasgow research team developed a system that uses a single-pixel camera to take pictures. The one-pixel camera is smaller and cheaper than traditional digital cameras that have millions of pixels, and can also see frequencies that are beyond the visible light spectrum.

So how can a one-pixel camera create a 3D image of an object? The research team used four such cameras and a separate lighting system in their experiment, which first required the creation of a detailed 2D image that was then converted to 3D.

First, the four cameras are set up around the object and the light projector starts beaming black and white patterns onto the object. The scientist in charge of the project, optics professor Miles Padgett, described the patterns as being “like a crossword puzzle.”

The idea is that the amount of white light reflected back onto the one-pixel camera indicates exactly how much white overlaps with the object. The more white squares overlap, the more intense the light that is reflected back to the cameras, Padgett explained.

The readings are then combined with the shapes into an algorithm that produces a 2D image of the object. By putting together the readings from all the four single-pixel detectors, scientists were able to create a full 3D image of the object. The technique they used is called shape from shade.

The single-pixel camera system is more efficient than traditional multi-pixel cameras, because it does not require calibration and creates accurate images in just a few seconds. Conventional imaging systems require a great deal of accuracy and calibration to turn 2D into 3D images.

What further distinguishes the single-pixel camera is that it is able to detect light that goes beyond the regular spectrum, from infrared to X-ray light. Most traditional 3D imaging devices cannot do this, and those that do have a wider perception range are very expensive.

Which takes us to the most attractive feature of the Glasgow scientists’ invention: the single-pixel camera will be really inexpensive, costing only a few dollars, while traditional 3D systems that produce the same results cost tens of thousands.

Scientists say a portable version of the camera can be developed quite easily, and that its low cost along with the ability to see beyond the regular light spectrum will make it very useful for a number of industries. The system could be used in medical imaging to help doctors find tumors in a patient, but also in the oil and gas industry, to detect leaks underground, for instance.

[Image via Extremetech]