" Pujiang-1” satellite was successfully launched by the ChangZheng-11 vehicle from the JiuQuan Satellite Launch Center

China on September 25

2015. The camera subsystem is one of the key payloads of the " Pujiang-1” satellite. The optical system

the pointer mirror mechanism

and the electronics of the camera were designed and produced under the concept of integration and miniaturization

which led to the compact

small

and light weight structure of the camera. With the novel design of the off-axis three-mirror reflective optical system

the camera includeda larger field of view and higher MTF value without a cover compared with the traditional coaxial system. By optimizing the layout of the optical elements

small volume was achieved. The difficulty of mechanical design and alignment was also reduced by optimizing the tolerance of the optical system. Additionally

this optical system was designed without a focusing mechanism but it could still address imaging needs because the back focal length was insensitive to the spacing change of the mirror. The camera used the pointer mirror mechanism to realize multi-target rapid pointing

enabling the capturemulti-target in each single imaging cycle

thereby shortening reaction time and improving imaging efficiency. The pointer mirror mechanism adopted the motor and gear set drive mode. The photoelectric encoder was installed coaxially with the mirror

with which the point angle can be precisely and accurately measured. In the electronic part

several functions

such as video imaging

image compression and coding

remote telemetry

temperature control

and power supply and distribution were integrated into one device. Standard plug-and-play 1553B communication and small-shape high-speed SpaceWire transmission interfaces were adopted to achieve rapid assembly and testing equipment in line with the modular design trend. The integrated circuit design reduced the number of devices

the overall system volume

system weight

and power consumption. After the satellite operating in-orbit

the in-orbit commissioning process was optimized combined with user needs. All the test and evaluation work were completed within one month.The camera normallyoperated with superior performance until today. The successful development of this camera and in-orbit stable operation provides a strong technical support for the follow-up high-performance light and smart cameras.