You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither SPIE nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the SPIE website.
4 March 2016Developments of VCSELs for printers and optical communications at Fuji Xerox
We review the characteristics of vertical-cavity surface-emitting lasers (VCSELs) for use in printers and optical
communications. In 2003, we launched the world's first laser printer with a 780-nm single-mode 8×4 VCSEL array
introduced to the light exposure system in order to meet the market demands for improving the image quality and speed
for laser printers. The design of the VCSEL array enabled us to increase the pixel density and the printing speed by
projecting 32 beams at a time to the photoconductor in the exposure process. High uniformity with less than 5% of
variation has been achieved for both the optical output and the divergence angle. Currently, our high-end color printer is
capable of producing the resolution of 2400 dpi (dots per inch) at the speed of 137 ppm (pages per minute). In the field
of optical interconnections and networks, 850-nm VCSELs are needed as high-speed optical transmitters (≥10Gbps). In
order to address communication traffic that will increase further as well as to reduce their power consumption to an even
lower level, we assessed the lasing characteristics of 850-nm VCSELs with InGaAs strained quantum-well (QW) active
layers by changing the ratio of Indium composition. As a result, we succeeded in reducing the power consumption per bit
to 43 fJ/bit at 10-Gbps, which is much lower than that of commercial GaAs QW VCSELs. Also, we studied 850-nm
transverse-coupled-cavity VCSELs, which enabled us to achieve a high 3dB modulation bandwidth (>23 GHz) and
realize eye-openings at the large-signal modulation rate of 36 Gbps.