Abstract
In this work, we report an expedient auto-collimating method for self-measuring the internal parameters (IPs) of optical cameras. Several key optical components, including the thin optical fibre (TOF), reflecting prism, and receiver, are introduced into optical cameras. The TOF outgoing end and area-array image receiver are integrated onto the focal-plane assembly of optical cameras. Different wavelengths of light, which are emitted by external sources, are transmitted to the focal plane through optical fibres. Because one optical fibre can transmit different wavelengths of light, the same position on the focal plane can obtain point light sources (PLSs) with different wavelengths. Then, the optical system of the cameras spontaneously transforms the PLSs into auto-collimating lights. The auto-collimating lights are reflected by a two-plane prism, return to the camera optical system, reach the focal plane and are received by the area-array sensor. Finally, the IPs are calculated based on a mathematical model of the imaging relation between fibre light sources and images. The experiment confirms that this method is efficient and has a level of precision of dozens of micrometres for an optical camera with a short focal length and small field of view. Our method is suitable for on-orbit IP measurements for cameras without spatial or temporal limitations.
Highlights
The position determination accuracy based on images is an important technique index of space optical cameras
Retaining the original optical system and charge coupled devices (CCDs) image sensor of the camera, we introduce the optical fibre and area-array complementary metal oxide semiconductor (CMOS) sensor into the focal plane of the camera to measure the internal parameters
We propose a new method for self-measuring internal parameters of remote sensing cameras without spatial or temporal limitations in real time
Summary
The position determination accuracy based on images is an important technique index of space optical cameras. We propose a high-efficiency self-measurement method for the internal parameters of optical cameras without spatial or temporal limitations. Retaining the original optical system and CCD image sensor of the camera, we introduce the optical fibre and area-array CMOS sensor into the focal plane of the camera to measure the internal parameters. The light (orange line in Fig. 1) of ground target reflection and radiation passes through the TMA system and is sensed by the CCD sensor to complete the on-orbit imaging. The output end of the optical fibre and the area-array CMOS image sensor are installed on the focal-plane assembly of the optical camera. The auto-collimating lights (red and blue lines in Fig. 1) are reflected by the two-plane prism and return to the camera optical system. The auto-collimating image of two colour points at the same position is recognized by the CMOS image colour
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
