The coupled DBR LED with one DBR for reflecting normal incidence light and the other for reflecting inclined incidence light has been grown by MOCVD. For improving the conventional DBR which was used to increase light...The coupled DBR LED with one DBR for reflecting normal incidence light and the other for reflecting inclined incidence light has been grown by MOCVD. For improving the conventional DBR which was used to increase light extraction efficiency in AIG-alnP red light LED is analyzed. At 20 mADc injection current, the LED peak wave length is 630 nm, and the light intensity of on axis is 137 mcd. The output light power is 2.32 mW. The light intensity and output light power have been improved compared with the conventional LEDs.展开更多
This work presented a demonstration of the potential for a fiber based cavity ring-down （CRD） using an optical time-domain reflectometer （OTDR）. The OTDR was used to send the impulses down into about 20km of a sta...This work presented a demonstration of the potential for a fiber based cavity ring-down （CRD） using an optical time-domain reflectometer （OTDR）. The OTDR was used to send the impulses down into about 20km of a standard single optical fiber, at the end of which the fiber cavity ring-down was placed. The OTDR measured no appreciable losses, so other CRDs multiplexed could be spliced in parallel along the same optical fiber. To demonstrate the behavior and sensitivity of the proposed configuration, a displacement sensor based on a fiber taper with a diameter of 50 μm was placed inside the fiber loop, and the induced losses were measured on the CRD signal -- a sensitivity of 11.8 ＋ 0.5 μs/mm was achieved. The dynamic range of the sensing head used in this configuration was about 2 mm. Finally, this work was also compared with different works published in the literature.展开更多
基金supported by Beijing Science and Technology Committee (project number D0404003040221)
文摘The coupled DBR LED with one DBR for reflecting normal incidence light and the other for reflecting inclined incidence light has been grown by MOCVD. For improving the conventional DBR which was used to increase light extraction efficiency in AIG-alnP red light LED is analyzed. At 20 mADc injection current, the LED peak wave length is 630 nm, and the light intensity of on axis is 137 mcd. The output light power is 2.32 mW. The light intensity and output light power have been improved compared with the conventional LEDs.
文摘This work presented a demonstration of the potential for a fiber based cavity ring-down （CRD） using an optical time-domain reflectometer （OTDR）. The OTDR was used to send the impulses down into about 20km of a standard single optical fiber, at the end of which the fiber cavity ring-down was placed. The OTDR measured no appreciable losses, so other CRDs multiplexed could be spliced in parallel along the same optical fiber. To demonstrate the behavior and sensitivity of the proposed configuration, a displacement sensor based on a fiber taper with a diameter of 50 μm was placed inside the fiber loop, and the induced losses were measured on the CRD signal -- a sensitivity of 11.8 ＋ 0.5 μs/mm was achieved. The dynamic range of the sensing head used in this configuration was about 2 mm. Finally, this work was also compared with different works published in the literature.
