918D-ST Series Wand Style Calibrated Photodiode Power Sensors
918D-ST Series Wand Style Calibrated Photodiode Power Sensors
918D-ST Series wand-style slim photodiode optical power sensors are ideal for measurements in a tight space with busy setups and are NIST-traceable calibrated for use with newport power meters. They feature a built-in, switchable attenuator with an On/Off sensor for the power meter and a temperature sensor to adjust for temperature dependent responsivity changes.
- NIST traceable calibration with lowest uncertainty available
- Switchable internal attenuator with On/Off position sensor
- Internal temperature sensor for thermal drift compensation
- Protective and rugged hand held aluminum housing
- Perfect for space tight applications See All Features
| Compare | Description | Drawings, CAD & Specs | Avail. | Price | ||
|---|---|---|---|---|---|---|
 | 918D-ST-IR 918D Wand Style Photodiode Power SensorsPower Detector, Wand-Style, Germanium, 780-1800 nm, OD3 Attenuator, DB15 | |||||
| 918D-ST-SL 918D Wand Style Photodiode Power SensorsPower Detector, Wand-Style, 400-1100 nm, OD3 Attenuator, DB15 | |||||
 | 918D-ST-UV 918D Wand Style Photodiode Power SensorsPower Detector, Wand-Style, UV-Si, 200-1100 nm, OD3 Attenuator, DB15 |
Compatible Power Meters
Newport offers a comprehensive range of optical power meters from low cost, hand-held meters to the most advanced dual-channel benchtop meter available in the market. Presented here is a list of meters compatible with the 918D Series sensors. For more detailed information about our power meters, please see our Optical Power Meter Guide.
 1938-R/2938-R |
 1936-R/2936-R |
 1919-R |
 843-R/843-R-USB |
 845-PE-RS |
 844-PE-USB |
|
|---|---|---|---|---|---|---|
| User Interface | Touchscreen | Advanced | Advanced | Simple | User Commands, PMManager | PMManager only |
| Temperature Sensing | ✔ | ✔ | ✔ | ✔ | ✔ | |
| Automatic Attenuator Sensing | ✔ | ✔ | ✔ | ✔ | ✔ | |
| Measurement Capabilities | Power (15 Hz) Fast Power (10 kHz) Low Frequency Power Pulsed Power Peak-to-Peak Power, RMS Power, Exposure, Current |
Power Peak-to-Peak Power, RMS Power, Current |
Power, Exposure |
Power | Power Low Freq. Power |
Power Low Freq. Power |
| Analog Bandwidth | Up to 200 kHz | Up to 400 kHz | 15 Hz | 15 Hz | 15 Hz | 15 Hz |
| Data Storage | 2 GB internal, External USB memory stick, Via PMManager |
250,000 pts internal | Limited by USB memory size | 843-R-USB: Via PMManager 843-R: None |
Via PMManager | Via PMManager |
| Measurement Rate per Second | Normal: 15 Fast Mode: 10,000 |
10,000 | 15 | 15 | 15 | 15 |
| Trigger In/Out | ✔ | ✔ | ||||
| Analog Out | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
| Computer Interface | USB RS232 |
USB RS232 |
USB RS232 |
843-R-USB: USB 843-R: None |
RS232 | USB |
Please refer to Newport Power Meter and Detector Legacy and Compatibility for a complete list of meters that are compatible with this model.
Specifications
Features
Excellent Photodiode Linearity
These photodiodes show excellent linearity over a large dynamic range. This is ideal for use in applications that require high accuracy measurements down to the pW level, especially when combined with a high sensitivity power meter that can accommodate the large dynamic range of the optical signal.
Responsivity Variation over Temperature
A natural characteristic of a photodiode is for the its optical response to change as the temperature changes near the bandgap of semiconductor materials. Newport’s 918D series sensors feature a thermocouple near the photodiode, which allows certain Newport meters to read the temperature and automatically adjust the responsivity, ensuring the most accurate measurements.
Factors that Affect Maximum Measurable Power
The maximum measurable power of photodiode sensors is dependent on several factors such as the wavelength of incoming light, photodiode current output saturation, temperature, use of an attenuator and a power meter's maximum current input value. Newport provides maximum power specifications based on the power meter models, with and without an attenuator, and wavelength-dependent maximum power level. With these factors affecting measurable power in mind, choosing the proper detector for your application is critical.
Switchable Attenuation Filter with On/Off Sensor
918D Series photodiode sensors feature a built-in attenuation filter that is engaged with an On/Off switch. Compared to our earlier 818 Series detectors with a removable threaded OD3 attenuator there are no worries about misplacing it. An attenuator On/Off position sensor lets connected Newport power meter models 1936-R, 2936-R, 1919-R and 841-PE-USB know when the attenuator is present so the the power readings can automatically be adjusted. 918D sensors are available with OD1 (10x), OD2 (100x), or OD3 (1000x - except for the UV model) attenuators.
NIST-traceable Sensor Calibration
Our calibrated photodiode sensors include a full spectral response calibration utilizing NIST-traceable standards calibrated with high-precision equipment maintained in Newport’s optical detector calibration facility. Tight calibration facility and process control allows the tightest calibration uncertainty in industry. Each detector is shipped with the calibration data, which is electronically stored inside the detector's EEPROM. A certificate of calibration as well as the actual calibration curves and data are shipped with each detector for attenuator and no attenuator models. To maintain accuracy and guarantee performance, Newport recommends annual photodiode detector calibration.
Wide Dynamic Range with OD3 Attenuator
The OD3 attenuators built in the housing extend the calibrated optical dynamic range of our detectors by three decades. Both the attenuator and detector have their serial number scribed on the part which, to maintain calibration, must match. Our attenuator design provides high damage threshold and spectral flatness. With the low noise equivalent power (NEP) associated with the photodiodes being used, a wider dynamic range is achieved. The clear aperture of the 884 Series attenuators is 10.3 mm.
Internal Temperature Sensor
The internal temperature sensor on the detector head is used to compensate the responsivity drift caused by the temperature change in the photodiode. The responsivity change is most sensitive around the bandgap, or towards the longer wavelength limit. The power meter calculates the temperature and automatically updates the responsivity value so that the measurements remain accurate. This feature is enabled with the power meter models 1936-R, 2936-R, 1919-R, and 844-PE-USB.
Post-Mountable for Steady Positioning
The sensor can be placed in a fixed, steady position by mounting it on an optical post. Each wand detector includes 8-32 and M4 mounting holes on both sides of the device for versatility in placement within optical systems.
Clear Anodization for UV Detectors
Newport’s 918D-ST-UV and 818-ST2-UV/DB are offered in clear, anodized aluminum housings for maximum durability in harsh environments and to avoid laser burns, particularly in the UV range. The plastic materials in which many competitors' wand detectors are packaged are highly absorbent to high power laser beams, especially in the short UV wavelength range, potentially evaporating materials and causing damage to UV wavelength optical coatings.
Resources
Literature
Maximum Measureable Power for Photodiode Detector(438.4 kB, PDF) Wand_Detectors_Datasheet(1.5 MB, PDF)
Technical Notes
Other
918D Series EU27 CE Declaration of Conformity(189.7 kB, PDF)
