  Single-pixel imaging (SPI) uses a single-pixel detector to create an image of
an object. SPI relies on a computer to construct an image, thus increasing both
the size and cost of SPI and limiting its application. We developed instant
single-pixel imaging (ISPI), an on-chip SPI system that implements real-time
imaging at a rate of 25 fps. ISPI uses the instant ghost imaging algorithm we
proposed which leverages signal differences for image creation. It does not
require a computer, which greatly reduces its cost and size. The reconstruct
time of ISPI for image creation is almost zero because little processing is
required after signal detection. ISPI paves the way for the practical
application of SPI.
