Entangled-photon compressive ghost imaging

We have experimentally demonstrated high-resolution compressive ghost imaging at the single-photon level using entangled photons produced by a spontaneous parametric down-conversion source and using single-pixel detectors. For a given mean-squared error, the number of photons needed to reconstruct a two-dimensional image is found to be much smaller than that in quantum ghost imaging experiments employing a raster scan. This procedure not only shortens the data acquisition time, but also suggests a more economical use of photons for low-light-level and quantum image formation.

Figure 1

Schematics for (a) compressive single-photon imaging and (b) compressive quantum ghost imaging. Insets: the corresponding Klyshko pictures.

Figure 2

Setup for compressive quantum ghost imaging. PBS, polarizing beam splitter; SLM, spatial light modulator; L, imaging lens; HWP, half-wave plate; BBO, $\beta$-barium borate crystal. A and B represent bucket detectors used for coincidence measurement. Inset: example of a two-dimensional random binary pattern impressed onto the SLM.

Figure 3

Reconstructed ghost image of (a) the Greek letter $\Psi$ and (b) the UR logo. The insets show the masks used in the test arm of the ghost imaging setup. (c) and (d) The absolute value of the calculated two-dimensional discrete cosine transforms of the insets in (a) and (b), respectively.

Figure 4

Calculated mean-squared error of the reconstructed ghost images of the UR logo (•) and $\Psi$ (✦) as functions of the number of measurements $M$.

Figure 5

Calculated signal-to-noise ratio of the reconstructed ghost images of the UR logo (•) and $\Psi$ (✦) as functions of the number of measurements $M$.