Luna LPD 100 Multichannel Log Detector for High Dynamic Range Optical Power Measurement
Two- or four-channel logarithmic photodiode amplifier calibrated from below -85 dBm to above +10 dBm with response up to 4 MHz.
- Operating wavelength range
- 1000nm - 1680nm
- Fiber type
- SM
- Optical connector type
- FC/APC
- Tested optical dynamic range
- -85 dBm - +10 dBm
Overview
The Luna LPD 100 Log Detector is a photodiode amplifier designed to measure low optical power levels and produce an electrical output signal that is linear with the logarithm of optical power. It is offered in two-channel and four-channel versions.
The LPD 100 is suited to high dynamic range power measurements in closed-loop applications. One example is polarization tracking, particularly when tracking to a minimum light level, where generating a reliable feedback signal for the tracker can be difficult.
Log amplifier design
The LPD 100 uses a log amplifier design with a large dynamic range and fast response. Each channel provides a single buffered analog voltage output on an SMA connector. The manufacturer's datasheet gives separate linear transfer functions relating output voltage to optical power in dBm for the -85 to 0 dBm and 0 to 10 dBm ranges.
Key Features
- Calibrated from < -85 dBm to > +10 dBm
- Response up to 4 MHz
- Single buffered analog (SMA) voltage output
- Two- or four-channel versions
- Compact size
- Modular design
Specifications
| Operating wavelength range |
1000nm - 1680nm
LPD 100-x-10-FC/APC is tested at 1060 nm; LPD 100-x-35-FC/APC is tested at 1310 nm and 1550 nm. An earlier datasheet revision lists 1200-1680 nm.
|
|---|---|
| Fiber type | SM |
| Optical connector type | FC/APC |
| Tested optical dynamic range |
-85 dBm - +10 dBm
Page labels this 95 dB; the datasheet row is titled 'Detected Optical Dynamic Range is 100dB' with the same -85 to +10 dBm limits.
|
| Output offset | -0.6 ± 0.2 V |
|---|---|
| Output voltage max @ 10 dBm | 2.5 ± 0.1 V |
| SMA port output impedance | 50Ω |
| Frequency response range |
0.1MHz - 4MHz
Optical power -85 ~ 10 dBm
|
| Transfer function (-85~0 dBm) | Vout = 0.0199 × Optical Power [dBm] + 2.2999 |
| Transfer function (0~10 dBm) | Vout = 0.0170 × Optical Power [dBm] + 2.2999 |
| Power supply | AC 100~240V / 15VA |
|---|---|
| Operating temperature | 0°C - 50°C |
| Storage temperature | -20°C - 70°C |
| Dimensions |
230mm (L) x 240 mm(W) x 60mm (H)
Specifications apply at ambient temperature T = 25°C and at center wavelength unless otherwise noted.
|
Specifications are taken from the manufacturer's documentation. See the datasheet for complete and current values.
Applications
- TE/TM polarization alignment
- PIC testing
- Polarization tracking
- Directed laser energy
- Closed-loop high dynamic range power measurements
Options & Accessories
| Option | Description |
|---|---|
| LPD-100-2-10-FC/APC | Dual Channel Log Detector, 1060 nm — Dual Channel Log Detector (95 dB dynamic range), 1060 nm, FC/APC connectors, and single SMA (buffered) outputs. |
| LPD-100-2-35-FC/APC | Dual Channel Log Detector, 1310/1550 nm — Dual Channel Log Detector (95 dB dynamic range), 1310/1550 nm, FC/APC connectors, and single SMA (buffered) outputs. |
| LPD-100-4-10-FC/APC | Four Channel Log Detector, 1060 nm — Four Channel Log Detector (95 dB dynamic range), 1060 nm, FC/APC connectors, and single SMA (buffered) outputs. |
| LPD-100-4-35-FC/APC | Four Channel Log Detector, 1310/1550 nm — Four Channel Log Detector (95 dB dynamic range), 1310/1550 nm, FC/APC connectors, and single SMA (buffered) outputs. |