High performance planar lightwave circuit triplexer with passive optical assembly

Abstract

High performance, compact planar lightwave circuit based triplexers have been built and tested. The triplexers utilize lasers, photodiodes and filters that have been adapted to enable passive optical assembly of the triplexer, 02005 Optical Society o f America OCIS codes: (130.3120) integrated optics devices (230.0250) optoelectronics ' IntroductionPassive optical networks (PONS) are beginning to be mass deployed in high speed Fiber to the Home (FTTH) access networks. These networks utilize bidirectionaI optical modules that allow downstream and upstream traffic to share a single fiber. In the case where voice, data, and video services are provided on the access network, the optical module on the subscriber side is a triplexer that has two downstream receivers and one upstream laser. The most widely used waveIength plan uses the band from 1550-1560 nm for downstream video, 1480-1500 nm for downstream data, and 1260-1360 nm for upstream data. A triplexer typically consists of a data photodiode and transimpedance amp, a video photodiode, a 13 10 nm band laser and monitor photodiode, and WDM filters to separate the various optical wavelengths. Proper operation of the triplexer requires a high level of optical isolation from the WDM filters as well as effective suppression of stray light. Because every subscriber has a triplexer as part of the Optical Network Termination (ONT) equipment, cost is also an extremely important parameter for triplexers.In this paper we describe a pIanar lightwave circuit (PLC) based triplexer that achieves high levels of performance fiom a compact design that is built entirely using passive optical assembly methods. Planar Lightwave Circuit Triplexer Design . .A PLC based optical triplexer can be viewed as being built from five distinct functional elements. The optical waveguide network provides optical connectivity between the other main elements. The remaining four elements are the Iaser, PDs (3 per triplexer), the WDM filters (two per triplexer), and the optical fiber. A challenge in designing a PLC based ttiplexer is the design of the interfaces between the optical waveguides and these other elements. In this section, we describe ow designs for the key elements and the interfaces. The optical waveguide network used in the triplexer is primarily based on silica waveguides formed on a silicon substrate [ 1 ,a]. The Filter yA Laser Data. PD MPD

Fiber to the Home Using a PON Infrastructure

“…8. As packaging and integration technologies have matured, the package size and performance of these devices have been steadily improving [26]- [28].…”

Silicon-based on-chip diplexing/triplexing technologies and devices

“…46) and SiO 2 (∼1.45), which could lead to the sub-micro cross section as well as the sharp waveguide bends. Furthermore, due to the potential to achieve monolithic optoelectronic integrated circuits, the silicon-based diplexer/triplexer could be integrated with laser diode and photodetectors to realize the integrated optical transceiver module [12][13][14]. Thus, on-chip silicon-based diplexing/triplexing technologies and devices have attracted much attention and achieved great progress in recent years.…”

Silicon-on-insulator platform for building fiber-to-the-home transceivers

“…In this approach, commodity discrete components, such as micro-lenses, thin-film filters, laser diodes and photodetectors are assembled into a package using active alignment and labor-intensive assembly techniques. In an effort to reduce assembly costs, several research groups proposed customizing lasers, photodetectors, and thin film filters to enable passive optical assembly of bi-directional transceivers on a planar lightwave circuit (PLC) platform [1]. To date, bidirectional PLC transceivers have been successfully realized in both InP [2] and silica-on-silicon [3][4][5] material systems.…”