In this paper, a novel fiber bundle probe which can transfer energy and provide a real-time feedback signal of fiber positions simultaneously is proposed and demonstrated experimentally to improve the fiber positioning accuracy of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). The fiber bundle probe is composed of four asteroid cores around a transmitting energy core at the center of the fiber bundle probe. The excitation characteristics were investigated numerically when a light spot illuminates on the end of the five-core fiber bundle probe. The calculated result shows that the fiber bundle probe can provide a real-time feedback signal when the offset between the center of end of probe and the light spot is in the range of -349.5 ~ -99.5 μm and 99.5 ~ 349.5 μm. Then the fiber bundle probe is fabricated by stacking-capillary method.
A novel twin-core fiber connector has been made by using two pieces of gradient refractive index (GRIN) lenses. The coupling loss of this connector is analyzed and several impact factors, such as lens length, focusing length of the specific matching conditions are discussed. Those factors that cause more transverse displacement have much greater coupling loss sensitivity, and the system tolerance is also considered to evaluate the practicability and the fabrication technologies.
In this paper, we analyzed the mode field distributions of the seven-core fiber consisting of a central core and six symmetrically surrounding single mode cores in a common cladding by the finite element method (FEM). The excitation characteristics in the splicing process between the seven-core fibers were numerically investigated. The efficiency of the fundamental mode excited by the incident light was studied by calculating the excitation coefficients in two cases, in which a lateral offset and a rotation offset are introduced between the two fiber ends, respectively. The results show that the excitation coefficient of the fundamental mode decreases from 1.0 to 0.1816 when the lateral offset increases from 0 to 9 μm. Similarly, when the rotation offset increases gradually from 0º to 10º, the excitation coefficient of the fundamental mode in the six surrounding cores gradually and synchronously decreases from 1.0 to 0.1779, while that of the central core is always constant.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.