Compare Model Drawings, CAD & Specs Wavelength Range 3 dB Bandwidth Maximum Conversion Gain Peak Responsivity NEP Availability Price
In Stock
320-1000 nm DC to 125 MHz 2x104 V/W 0.5 A/W @ 800 nm 3.3 pW/√Hz
In Stock
320-1000 nm 25 kHz to 125 MHz 2x104 V/W 0.5 A/W @ 800 nm 3.3 pW/√Hz
In Stock
900-1700 nm DC to 125 MHz 4x104 V/W 1.0 A/W @ 1550 nm 2.5 pW/√Hz
In Stock
In Stock
900-1700 nm 25 kHz to 125 MHz 4x104 V/W 1.0 A/W @ 1550 nm 2.5 pW/√Hz
In Stock


  • Detector Diameter
    1801: 0.4 mm
    1811: 0.1 mm
  • Detector Material
    1801: Silicon
    1811: InGaAs
  • Detector Type
  • Fiber-Optic Connector
  • Fiber Type
    Singlemode or Multimode
  • Maximum Transimpedance Gain
    4x104 V/A
  • Rise Time
    3 ns
  • Saturation Power
    1801: 110 µW @ 800 nm
    1811: 55 µW @ 1550 nm
  • Output Connector
  • Output Impedance
    50 Ω
  • DC Bias Monitor Bandwidth
    50 KHz (for -AC models only)
  • DC Bias Monitor Transimpedance Gain
    10 V/mA (for -AC models only)
  • DC Bias Monitor Output
    SMB (for -AC models only)
  • Power Requirements
    ±15 VDC, 250 mA
  • Thread Type
    8-32 (M4 adapter included)


Silicon or InGaAs Versions

Silicon models provide visible wavelength coverage from 320-1000 nm and use a silicon-PIN photodiode with a high-gain, low-noise transimpedance amplifier. The near-IR version uses an InGaAs-PIN photodetector that provides coverage from 900-1700 nm. These receivers will enable wide bandwidth low-noise detection of signals distributed over fiber-optic cables or found in high resolution spectroscopy, fiber-optic sensors, optical metrology and many other applications.

Typical responsivity of Model 1801 (Silicon) and Model 1811 (InGaAs) detectors.

High Transimpedance Gain and Low Noise

Because of their high transimpedance gain and low noise-equivalent power (NEP), they offer the best in sensitivity for signals with rise and fall times as short as 3 ns. This high sensitivity, combined with their high-level output, reduces the effects of downstream noise sources.

Typical frequency response (top) and noise floor (bottom) for Models 1801 and 1811.

DC Coupled Versions

With true DC coupling, these photoreceivers give linear responses to transient signals without artificial ringing, tails, or other anomalies.

AC Coupled Versions

AC-coupled versions with a low-frequency roll-off at 25 kHz are available. These photoreceivers are useful for measuring a small AC signal on a large cw component. To make alignment easier, AC-coupled versions are equipped with a DC photocurrent monitor output. The monitor output has a 50-kHz bandwidth and a gain of 1 V/mA.

RF Shielding

Careful RF shielding and filtering of power-supply inputs eliminate electromagnetic interference, even in laboratories with Q-switched lasers and other noisy equipment.