1 © 2017 Astro Ltd Printed in the UK
1. Introduction
In 1995, ghost imaging was rst realized in an experiment
with the help of entangled photon pairs [1, 2]. Bennink etal
rst presented their classical ghost imaging and interference
experiments by using classical coherent light, which showed
that quantum entanglement is not necessary to realize corre-
lated imaging in 2002 [3]. It was proved that the classical cor-
related light can achieve some peculiar effects of entangled
two photons [4]. Soon, Cheng etal theoretically put forward
a scheme for lensless Fourier-transform imaging with a clas-
sical correlated source, and discussed its application in x-ray
diffraction [5]. Compared with the entangled source, ghost
imaging with classical thermal light provided more poten-
tial applications, so the classical correlated imaging has been
studied extensively in recent years, both experimentally and
theor etically[5–10]. Very recently, two groups experimentally
realized x-ray ghost imaging [11, 12], which may open the way
for protocols to reduce radiation damage in medical imaging.
Many studies have focused on effectively improving the imag-
ing quality, such as compressive sensing [13, 14], high-order
ghost imaging [15, 16] and computational ghost imaging
[17, 18]. In addition, ghost imaging through atmospheric tur-
bulence has been discussed [19, 20].
Very recently, a unied analytical formula of point-spread
function (PSF) which can be applicable for different ghost
imaging systems has been presented [21]. By their results, the
difference of imaging resolution between different imaging
schemes can be predicted from PSF. Noted that the coherent-
mode representation of partially coherent elds can be used to
analyze imaging quality of correlated imaging [22, 23], three
kinds of ghost imaging schemes (2 − f, f − 2f, and lensless
ghost diffraction systems) were analyzed numerically under
the coherent-mode theory, while Cheng and Han only dis-
cussed the possibility that this theory was used to analyze the
three kinds of imaging schemes, respectively [22]. Thus one
can enquire ‘if the coherent-mode representation theory can
be used to analyze the difference of imaging quality between
different ghost imaging systems?’ In this paper, we apply
the coherent-mode representation to compare imaging qual-
ity between different imaging systems. It is shown that by
comparing the distribution difference of the decomposition
coefcients of the object between those imaging systems, one
can predict which system provides ghost-image with better
Laser Physics
Evaluating imaging quality between
different ghost imaging systems based
on the coherent-mode representation
QianShen, YanfengBai, XiaohuiShi, SuqinNan, LijieQu, HengxingLi
and XiquanFu
College of Computer Science and Electronic Engineering, Hunan University, Changsha 410082,
People’s Republic of China
E-mail: yfbai@hnu.edu.cn
Received 25 May 2017
Accepted for publication 25 May 2017
Published 23 June 2017
Abstract
The difference in imaging quality between different ghost imaging schemes is studied by
using coherent-mode representation of partially coherent elds. It is shown that the difference
mainly relies on the distribution changes of the decomposition coefcients of the object
imaged when the light source is xed. For a new-designed imaging scheme, we only need
to give the distribution of the decomposition coefcients and compare them with that of the
existing imaging system, thus one can predict imaging quality. By choosing several typical
ghost imaging systems, we theoretically and experimentally verify our results.
Keywords: ghost imaging, imaging quality, coherent-mode representation
(Some guresmay appear in colour only in the online journal)
Q Shen et al
Evaluating imaging quality between different ghost imaging systems based on the coherent-mode representation
Printed in the UK
075203
LAPHEJ
© 2017 Astro Ltd
27
Laser Phys.
LP
10.1088/1555-6611/aa771f
Paper
7
Laser Physics
Astro Ltd
IOP
2017
1555-6611
1555-6611/17/075203+5$33.00
https://doi.org/10.1088/1555-6611/aa771f
Laser Phys. 27 (2017) 075203 (5pp)