2 Gbit/s data transmission from an unfiltered laser-based phosphor-converted white lighting communication system

Abstract

El-Desouki, Munir M.; Speck, James S.; Nakamura, Shuji; Ooi, Boon S.; DenBaars, Steven P. Abstract:We demonstrate data transmission of unfiltered white light generated by direct modulation of a blue gallium nitride (GaN) laser diode (LD) exciting YAG:Ce phosphors. 1.1 GHz of modulation bandwidth was measured without a limitation from the slow 3.8 MHz phosphor response. A high data transmission rate of 2 Gbit/s was achieved without an optical blue filter using a non-return-to-zero on-off keying (NRZ-OOK) modulation scheme. The measured bit error rate (BER) was less than the forward error correction (FEC) limit of 3.50 × 10 -3 . The generated white light exhibits CIE 1931 chromaticity coordinates of (0.3628, 0.4310) with a color rendering index (CRI) of 58 and a correlated color temperature (CCT) of 4740 K when the LD was operated at 300 mA. The demonstrated laserbased lighting system can be used simultaneously for indoor broadband access and illumination applications with good color stability. Kruglov, and O. Ziemann, "GaN-based miniaturized cyan light-emitting diodes on a patterned sapphire substrate with improved fiber coupling for very high-speed plastic optical fiber communication," IEEE Photonics J., 4(5), 1520-1529 (2012). 24. D. Tsonev, S. Videv, and H. Haas, "Towards a 100 Gb/s visible light wireless access network,"

Semipolar GaN-based laser diodes for Gbit/s white lighting communication: devices to systems

“…10,15,45 Additionally, the spectral intensity of sunlight is lower in the NUV and violet spectral range than in the blue spectral range that is typically used for III-nitride emitters in solid-state lighting systems. As a result, NUV LDs enable VLC systems that can be robust in the presence of high intensities of sunlight, for example, in a room with many windows.…”

“…Contrary to previous work, an optical blue-filter was not required in the current LD-based white lighting setup as the current LD is not significantly affected by phosphor response based on our previous investigation. 15 The emitted photons are received at the 1 GHz avalanche photodetector (APD, Menlo System APD 210), which is placed 15 cm from the emitted light. The reason to choose 1 GHz APD is to collect diffused white emission at large active area rather than 10 GHz p-i-n PD used in previous section.…”

“…Even though the response in LEDs suffers from comparatively slow relaxation lifetimes of phosphors, LDs with phosphors have shown OOK data rates of 2 Gbit/s without significant negative effects from the color converting process. 15,16 Many advantageous merits of LDs over LEDs point to the need for more advanced studies of LDs for VLC.…”

Semipolar InGaN-based superluminescent diodes for solid-state lighting and visible light communications

“…Besides, the utilization of III-nitride LEDs and LDs as the transmitter for free-space visible light communications (VLC) and underwater wireless optical communications (UWOC) has been demonstrated and investigated recently [13][14][15][16]. Compared to the conventional radio frequency (RF) communication techniques, VLC shows many potential advantages, such as unregulated channels, avoiding electromagnetic interference (EMI), high security and low-cost [13,15]. Hence, by combining GaN-based LEDs or LDs with phosphors, the white light bulb can be achieved for SSL and VLC functionalities [12,15].…”

“…Compared to the conventional radio frequency (RF) communication techniques, VLC shows many potential advantages, such as unregulated channels, avoiding electromagnetic interference (EMI), high security and low-cost [13,15]. Hence, by combining GaN-based LEDs or LDs with phosphors, the white light bulb can be achieved for SSL and VLC functionalities [12,15].…”