Reflection Probes

Wavelength Range 200-2500 nm; Number of fibers 7-19; Core diameter 200-400 µm; Connector type SMA-905

Reflection probes are utilized to gather spectral data from diffuse or specular materials. Light from a source is directed through six illumination fibers to the sample, with the reflection measured by a seventh fiber at the center of the probe tip. Explore our reflection probes below.

Reflection Probes
Reflection probes are used to obtain spectral information of diffuse or specular materials. Light from a source is directed through six illumination fibers to the sample, and the reflection is measured by a seventh fiber at the center of the probe tip. This seventh fiber is connected to a spectrometer configured for the relevant wavelength range. Additional illumination fibers can be added to increase the light source energy and enhance the reflection signal level. For measurements at a 90° angle, the FCR-90-Option was developed. This special adapter, with a mirror positioned at 45°, can be easily mounted on the tip of Avantes standard reflection probes. The FCR-COL is an adjustable UV/VIS/NIR collimating and focusing lens, enabling the focusing of the measurement spot at an extended distance.

Reflection Probes with Reference
To correct for fluctuations and drift from your light source, periodic referencing is necessary. Avantes offers a series of reflection probes with a self-referencing feature to facilitate this. Light from the source is bundled into 12 fibers, split into two 6-fiber bundles. One bundle is directed to the probe end for sample measurement, while the other is directed to a white reflection tile built into the probe for a light source reference. This reference leg is connected to a slave spectrometer channel dedicated to light source referencing or can be routed to a single channel via a fiber-optic (contact a Sales Engineer for this special configuration). The probe end has a seventh fiber that reflects light back to the master spectrometer channel.

Reflection Probes with Multiple Legs
For certain measurements, a reflection probe that can be coupled to two spectrometers and a light source is required. A typical example is a reflection measurement in the UV/VIS and NIR range. For these situations, Avantes offers reflection probes with multiple legs. Light from a source is coupled into a fiber bundle consisting of 17 illumination fibers, which transport the light to the probe end. The reflected light is uniformly distributed into two read fibers, each connected to a spectrometer. For measurements at a 90° angle, the FCR-90-Option is available. This adapter, with a mirror mounted at 45°, can be easily attached to the tip of these reflection probes. To accurately focus a small measurement spot from a greater distance, the FCR-COL adjustable UV/VIS/NIR collimating/focusing lens can be mounted to the tip of these probes.

Reflection Probes with Small Tips
For certain medical and semiconductor applications, a small or very small tip is advisable for conducting reflectance measurements. Avantes offers two standard diameters of small-tip reflection probes: 1.5mm and 2.5mm, each typically 100mm in length. The probe is configured with an illumination leg containing six 200 μm fiber cables connected to a fiber-coupled light source and a single 200 μm read fiber cable to measure the reflection via connection to a spectrometer. A special angled fiber holder (AFH-15) is available for the 1.5mm diameter reflection probe, enabling reflection measurements at angles of 15, 30, 45, 60, 75, and 90 degrees. Depending on application requirements, Avantes offers various jacketing options, including Kevlar-reinforced PVC sleeving with PTFE inner tubing (Standard), heavy industrial chrome-plated brass mono-coil, stainless steel (BX), silicone-coated stainless steel mono-coil (MS), flexible chrome-plated brass outer jacket with hooked profile (ME), and other special jacketings upon request. For high-temperature applications, special high-temperature epoxy (HT) is available and should be specified at the time of order.

Reflection Probes for Powders and Thick Fluids
Avantes offers a specially designed series of reflection probes for effectively measuring reflection in powders and thick fluids. These probes allow users to simply dip the probe into the powder or thick fluids to conduct measurements. The probe’s illumination leg is connected to a light source and carries light to the sample via a bundle of six fibers. At the probe tip, a 45-degree fused silica window illuminates the sample and collects indirect reflections, which are carried by a single fiber to the spectrometer. The 45-degree angle prevents direct back reflection from the window, thus improving the dynamic range of your measurement.

1/2" Industrial Reflection Probes for Powders and Thick Fluids
For industrial applications requiring reflection measurements in thick liquids or powders, this probe is ideal. The stainless steel cylinder and probe end withstand extreme conditions. The tip is exchangeable and waterproof, with optional materials like PEEK or Hastelloy® C276 available. Light enters from the source through six bundled fibers to the probe end, illuminating the material through a sapphire window angled at 45 degrees. This angle prevents light reflection from the window. The light is selectively reflected through the seventh fiber in the probe, which leads to the connected spectrometer.

Applications: Gathering spectral data from diffuse or specular materials