Santec OTF-950 C Band Optical Tunable Filter DWDM Bandpass Fiber Optic Tester

Santec OTF-950 C Band Optical Tunable Filter DWDM Bandpass Fiber Optic Tester: Independent Wavelength and Bandwidth Tuning with Flat-Top Filter Shape

The Santec OTF-950 C Band Optical Tunable Filter DWDM Bandpass Fiber Optic Tester is a versatile bench-top optical tunable filter that allows both wavelength tuning and passband width selection simultaneously and independently. Built around unique precision free-space optics and an accurate tuning mechanism, it delivers excellent optical control and a flat-top passband shape, making it a fit for next generation bundle wavelength OXC applications and flexible test and measurement work in the C-band.

Key Features and Benefits of the Santec OTF-950 C Band Optical Tunable Filter DWDM Bandpass Fiber Optic Tester

• Independent center wavelength and bandwidth tuning — Adjust center wavelength and passband width simultaneously and independently, providing flexibility that fixed-bandwidth tunable filters cannot match.
• 40 nm wavelength tuning range — Covers a wide span of the C-band from a single filter for DWDM channel selection and component characterization.
• 0.25 to 6.0 nm bandwidth tuning range — Adjust the -3 dB passband from narrow filtering suitable for single-channel isolation to wide filtering suitable for multi-channel or ASE noise measurements.
• Flat-top filter shape — High figure of merit passband delivers uniform transmission across the filter bandwidth, minimizing spectral distortion of the signal being filtered.
• Free-space optics design — Unique precision free-space architecture provides the optical control needed to hold both flat-top shape and accurate tuning across the full range.
• 0.02 nm typical wavelength accuracy — Precise wavelength positioning supports ITU-grid channel selection in 50 GHz DWDM systems.
• Low insertion loss — Typical 5 dB insertion loss preserves signal budget when the filter is inline with other test equipment.
• Low PDL and PMD — Typical 0.25 dB PDL and 0.2 ps PMD keep the filter from adding measurable polarization effects to sensitive measurements.
• High return loss — Typical 45 dB return loss (40 dB minimum) minimizes back reflections into the source under test.

Advanced Capabilities

The OTF-950's ability to tune center wavelength and bandwidth independently is the defining engineering choice. Most tunable filters offer one or the other — either a fixed-bandwidth filter that sweeps across wavelength, or a fixed-wavelength filter with adjustable bandwidth. The OTF-950 provides both axes of control in one instrument, which means a single filter can be reconfigured on the fly to isolate a narrow DWDM channel, measure amplified spontaneous emission across a wide window, or sweep the passband shape across a device under test to characterize its wavelength response.

The flat-top filter shape is the other technical strength worth calling out. The datasheet specifies typical -3 dB bandwidth control down to 0.25 nm and typical -20 dB bandwidth of 0.70 nm, indicating a sharp transition from passband to stopband. A high figure of merit — the ratio between -3 dB and -20 dB bandwidths — is what separates a useful tunable filter from a rounded Gaussian shape that lets adjacent-channel energy leak through. For applications like next generation bundle wavelength OXC development and DWDM component test, the flat-top shape is what makes measurements on the transition edges of adjacent channels meaningful.

Calibration and Quality Assurance

Every Santec OTF-950 is calibrated prior to shipping to OEM specifications. The order includes a Calibration Certificate, Calibration Label, and full Calibration Data. This means the instrument arrives traceable, audit-ready, and ready to use straight out of the box — no need to schedule a calibration cycle before putting it into service.

Specifications (50 GHz, C-band)

Specification	Min.	Typ.	Max.	Unit
Wavelength Tuning Range	40	—	—	nm
Bandwidth Tuning @ -3 dB	0.25	—	6.0	nm
Bandwidth Tuning @ -20 dB	0.70	—	6.5	nm
Wavelength Accuracy	—	0.02	—	nm
Insertion Loss	—	5	—	dB
Insertion Loss Uniformity	—	0.5	—	dB
PDL	—	0.25	—	dB
PMD	—	0.2	—	ps
Chromatic Dispersion	-40	—	40	ps/nm
Return Loss	—	45	—	dB