First experimental demonstration of temporal hypertelescope operation with a laboratory prototype

Abstract

In this paper, we report the first experimental demonstration of a temporal hypertelescope (THT). Our breadboard including eight telescopes is first tested in a manual cophasing configuration on a one-dimensional object. The point-spread function (PSF) is measured and exhibits dynamics in the range of 300. A quantitative analysis of the potential biases demonstrates that this limitation is related to the residual-phase fluctuation on each interferometric arm. Secondly, an unbalanced binary star is imaged, demonstrating the imaging capability of THTs. In addition, a two-dimensional PSF is recorded, even if the telescope array is not optimized for this purpose.

Phase-shifting technique for improving the imaging capacity of sparse-aperture optical interferometers

“…A second natural idea is to replace all the intermediate optical components of the relaying optics with single mode optical fibers: SMF present indeed the specific advantage of filtering all the entrance wavefront errors, and could also replace the bulk ODL subsystem as in the experiment described in Ref. [18]. Practically, they could be connected to the individual input and output sub-pupils of the interferometer by means of micro-lenses arrays having different geometries.…”

“…[18]. Practically, they could be connected to the individual input and output sub-pupils of the interferometer by means of micro-lenses arrays having different geometries.…”

“…A few variants of the Fizeau interferometer have already been proposed in order to improve the Signal to Noise Ratio (SNR) at the expense of a reduced Field of View (FoV) [15][16][17], and some other get rid of the opto-mechanical complexity by replacing most of the relay optics with monomode optical fibers [18]. But herein one of our main goals is to define an alternative optical design suitable for quick or "snapshot" imaging, applicable with any number N of telescopes, and that should stay independent of any technological solution (this point is further discussed in section 5.2).…”

Co-phasing of a diluted aperture synthesis instrument for direct imaging: Experimental demonstration on a temporal hypertelescope

“…An experimental validation of the THT principle was previously reported with this test-bench (Bouyeron et al 2010). However, the DR value obtained during this first experiment was unstable as function of time and reached a maximum value of 300.…”

“…This new architecture makes the instrument very versatile and well-suited to a space-based mission. We then developed a THT experimental test-bench with the support of CNES and Thales Alenia Space (Bouyeron et al 2010). The aim of this device is to experimentally demonstrate that a project of a space-based hypertelescope will be realistic in a few years.…”