New Technion research could make telescope resolution clearer - study
The research, published by a doctorate student and his supervisor, could make telescope image resolution clearer for the study of stars.
By JERUSALEM POST STAFFUpdated: JUNE 4, 2021 00:07Palestinian astronomical observers use telescopes to view the moon ahead of Ramadan to mark the beginning of the holy fasting month, April 12, 2021.(photo credit: REUTERS/MUSSA QAWASMA)
New research out of the Technion-Israel Institute of Technology could make the resolution of telescope images clearer.The research was led by Technion Ph.D. student Gal Gumpel and was supervised by Dr. Erez N. Ribak. It was published in the Journal of the Optical Society of America B, a peer-reviewed scientific optics journal on Thursday.Dr. Erez Ribak (Credit: TECHNION SPOKESPERSON'S OFFICE)The way that images are cast in a telescope is through the process of diffraction: The scattering of light rays – which also behave as waves – at specific angles across a surface. Their movement is detected by the telescope camera.The problem is the specific angle at which the rays are cast causes the observed object to appear blurry, without the ability to sharpen the image further.In the Technion team's research, for example, two stars studied through a microscope will look like two fuzzy spots, instead of showing up in all their detail.One way to increase resolution is to increase the telescope aperture, or the opening in the telescope through which light travels.Astronomical photons (white light particles), emitted by a star, pass the telescope aperture and reach a light amplifier containing atoms. An atom hit by a photon emits a larger number of identical stimulated photons (marked in green) that hit the telescope detector at a higher precision than that of the original stellar photon. At the same time, the amplifier emits spontaneous photons (marked in red) which scatter in all directions and hit the detector in such a quantity so as to create a constant background, hiding the stellar amplified photons. To overcome this limitation the researchers measured the average spontaneous emission by blocking the stellar light and taking a picture of the background alone. By subtraction of that background from a picture with the star light, they were able to reconstruct the image of the star at high resolution. (Credit: TECHNION SPOKESPERSON'S OFFICE)Gumpel and Ribak experimented with the amplification of photons, or light particles, to make the image of stars clearer.What happens to photons when they cross a telescope aperture and reach a light amplifier is that the amplifier creates copies of the original photon, identical in wavelength as well as direction, which improves the resolution of the image without changing its size, which means that it doesn't come out blurry.
This type of light amplification also leads to a spontaneous replication of the same photos –more than necessary.In their lab, Gumpel and Ribak measured the two images separately, giving them the ability to analyze the image more clearly.Ph. D. student Gal Gumpel. (Credit: TECHNION SPOKESPERSON'S OFFICE)However, "one of the possible drawbacks of the method is the loss of sensitivity in the final images," the researchers said, "but this is a worthy price to pay for the increased resolution."Read the published study here.
