Theoretical and experimental studies on the tilted fiber Bragg grating (TFBG) temperature and strain sensing characteristics are conducted. The TFBG is stuck to the surface of the beam along the axis direction. When t...Theoretical and experimental studies on the tilted fiber Bragg grating (TFBG) temperature and strain sensing characteristics are conducted. The TFBG is stuck to the surface of the beam along the axis direction. When the free end of the beam is forced, both the strain and temperature will induce wavelength shifts. The temperature characteristic of TFBG cladding modes is similar to that of the core mode while the strain characteristics of TFBG core mode and cladding modes are different. A novel method to discriminate the temperature and strain simultaneously is put forward based on TFBG sensing characteristics.展开更多
A method of color image single-channel encryption is proposed. The proposed method uses tricolor grating to encode a color image into a gray level image, then the gray level image is encrypted by double random phase e...A method of color image single-channel encryption is proposed. The proposed method uses tricolor grating to encode a color image into a gray level image, then the gray level image is encrypted by double random phase encryption, so a color image is encrypted in a single-channel and its security is ensured. Computer simulations and the chromatic aberration analysis are given to prove the possibility of the proposed idea.The optical system is simpler and is easy to be applied into practice. The simulation results show that this method is efficiency to encrypt a color image, and it is robust.展开更多
基金supported by the National Natural Science Foundation of China (No. 60736079)the Education Foundation of Tianjin (Nos.20060609 and 2006BA28)
文摘Theoretical and experimental studies on the tilted fiber Bragg grating (TFBG) temperature and strain sensing characteristics are conducted. The TFBG is stuck to the surface of the beam along the axis direction. When the free end of the beam is forced, both the strain and temperature will induce wavelength shifts. The temperature characteristic of TFBG cladding modes is similar to that of the core mode while the strain characteristics of TFBG core mode and cladding modes are different. A novel method to discriminate the temperature and strain simultaneously is put forward based on TFBG sensing characteristics.
基金supported by the Opening Subject of KeyLaboratory of Opoelectronic Information Science & Technology,Ministry of Education of China(Grant No. 2005-141)
文摘A method of color image single-channel encryption is proposed. The proposed method uses tricolor grating to encode a color image into a gray level image, then the gray level image is encrypted by double random phase encryption, so a color image is encrypted in a single-channel and its security is ensured. Computer simulations and the chromatic aberration analysis are given to prove the possibility of the proposed idea.The optical system is simpler and is easy to be applied into practice. The simulation results show that this method is efficiency to encrypt a color image, and it is robust.
