Ascentta Isolator Hybrid: Tap Coupler + Isolator

The TISO hybrid device from Ascentta is a fiber optic component that combines an optical isolator and a tap coupler in a single compact package. It is designed for 1310 nm or 1550 nm operation and provides high isolation on the main signal path while simultaneously extracting a small percentage of the optical power (tap) for monitoring or feedback. This helps protect laser sources from back‑reflections, stabilize system performance, and allow real‑time power monitoring in fiber optic transmitters, EDFAs, and other optical communication or sensing systems.

Key optical specifications include: - Operating wavelengths: 1310 ± 15 nm or 1550 ± 15 nm (single stage); 1310 ± 30 nm or 1550 ± 30 nm (dual stage) - Isolation (all SOP, 23 °C): 31 dB min / 40 dB typ for single stage, 45 dB min / 50 dB typ for dual stage - Insertion loss (signal channel, all SOP, 23 °C): 0.6 dB typ / 0.8 dB max for single stage, 0.8 dB typ / 1.0 dB max for dual stage - Tap port insertion loss (all SOP): 16.2–18.0 dB for 2% tap, 12.1–14.0 dB for 5% tap - Ripple: ≤ 0.5 dB - Polarization dependent loss (PDL): ≤ 0.15 dB - Polarization mode dispersion (PMD): ≤ 0.1 ps (≤ 0.25 ps for non‑compensated single stage) - Return loss: ≥ 55 dB - Optical power handling: up to 300 mW - Operating temperature: −5 to +70 °C; storage: −40 to +85 °C - Package size: 5.5 mm diameter × 35 mm length.

Ascentta uses the format TISO–[Wavelength]–[Stages]–[Tap Ratio]–[Fiber Type]–[Fiber Length]–[Connector]. Common options include: - Wavelength: 13 = 1310 nm, 15 = 1550 nm, X = other wavelengths on request - Stages: S = single stage, D = dual stage - Tap ratio: 01 = 1%, 02 = 2%, 03 = 3%, 05 = 5%, X = other custom ratios - Fiber type: B = SMF‑28, 250 µm; L = SMF‑28, 900 µm; X = others - Fiber length: 10 = 1.0 m, 15 = 1.5 m, 20 = 2.0 m, 30 = 3.0 m, X = other lengths - Connector: NE = none, FA = FC/APC, FC = FC/PC, SA = SC/APC, SC = SC/PC, ST = ST/PC, LA = LC/APC, LC = LC/PC, X = others Because connector choice can slightly affect insertion loss, return loss, and PDL, it is recommended to confirm your exact configuration and any special requirements directly with Ascentta sales before ordering.

Single‑stage TISO hybrids offer lower insertion loss on the main signal path (typically ~0.6 dB) with isolation of about 31 dB minimum. Dual‑stage hybrids use two isolation stages to provide significantly higher isolation (≥45 dB, typically ~50 dB) at the expense of slightly higher insertion loss (typically ~0.8 dB). Choose single stage when your system is power‑sensitive and can tolerate moderate isolation, such as short‑reach links or lower‑gain amplifiers. Choose dual stage when you need strong protection from back‑reflections or feedback, for example in narrow‑line lasers, high‑gain EDFAs, or long‑haul optical communication systems where reflected light can destabilize the source or degrade OSNR.

The built‑in tap coupler splits a small percentage of the forward signal power to a tap port, allowing you to monitor or control the optical power without inserting a separate coupler. Standard factory options include 1%, 2%, 3%, and 5% tap ratios, each characterized over all states of polarization. For example, the specified insertion loss ranges for the tap port are 16.2–18.0 dB for 2% and 12.1–14.0 dB for 5%. These taps are commonly used for automatic power control, performance monitoring, and safety interlock circuits in telecom, CATV, and fiber laser systems. Custom tap ratios can also be requested if you need a different monitoring level.

Hybrid isolator tap couplers like the TISO series are widely used anywhere you need both isolation and power monitoring in a compact form factor. Typical applications include EDFA input and output stages, fiber laser sources, transmitters in WDM systems, CATV distribution, and fiber‑optic sensor interrogation units. Integrating the isolator and tap coupler reduces the number of splices and components, which lowers overall insertion loss, improves reliability, saves space, and simplifies assembly compared to using a discrete isolator and a separate fiber coupler. The 5.5 × 35 mm package is especially suitable for high‑density modules and OEM integration.

The TISO hybrid is designed to be largely insensitive to input state of polarization, with low PDL (≤0.15 dB) and very low PMD (≤0.1 ps, or ≤0.25 ps for non‑compensated single‑stage parts). It supports continuous optical power levels up to 300 mW, which is suitable for most telecom and many fiber laser seeding or amplifier applications. The specified operating temperature range is −5 °C to +70 °C, with storage from −40 °C to +85 °C. For deployments in harsher environments, very high power levels, or wavelengths outside 1310/1550 nm, users should consult Ascentta to verify whether a customized version or different product family is more appropriate.