Probes

the probe is "where the rubber meets the road"

For many, the probe tip is the most important part of their Raman system; where clean laser light must exit and the collection of wavelength shifted Raman light must be efficient. EmVision has been working at the probe tip for more than a decade, and this skill is a core competency.

Raman Lensed Probe

A Decade of Performance

EmVision started as a custom probe designer and manufacturer, and this probe is an outcome of our early work and continues today as a mainstay of our probe product line. The Raman Lensed Probe has been used across many industries and in many different applications. Additionally, EmVision has produced dozens of different design variations over the years (please see below and Custom Designs).

The stainless steel probe tip has a 2.1 mm (0.083″) OD and is 10 cm (4″) in length. A removable wand with a 6.35 mm (0.25″) OD is available to make-it easier for a user to hold. The overall standard length is 1.5 m (5′).

The Raman Lensed Probe has a single laser emitting 300 µm fiber and seven 300 µm collection fibers that connect to the spectrometer. At their ends, the emitting fiber has a small band-pass filter and the seven collection fibers have a donut shaped long-pass filter that rejects the laser light. The probe tip’s outer contact surface can be either fused silica or magnesium fluoride and this is part of a two-piece lens (the second lens being either silica or sapphire). The optical elements are permanently fixed in alignment so there is no possibility of movement.

Since EmVision’s probes and “tip-to-chip” designs are optimally integrated through our multi-fiber connector and our spectrometer (HT or CS) to the camera / CCD chip, it is recommended that these EmVision components be used in combination to maximize performance of your Raman system.

Raman Endoscopic Probe

The Smallest Raman Probe

EmVision’s Raman Endoscopic Probe is the smallest Raman probe on the market, and incorporates the same general design as the Lensed Probe. The Endoscopic Probe has been utilized within animals and in the human body, and please see referenced peer reviewed articles on this website (e.g. Jan-2017 on in vivo inflammatory bowel disease). The small tip (both diameter and length) allows for endoscopic entry and maximum flexibility.

The stainless steel probe tip has a 1.65 mm OD and is 5 mm in length. The overall standard length is 3.0 m (10′). The Endoscopic Probe has a single laser emitting 200 µm fiber and ten 200 µm collection fibers that connect to the spectrometer. Again, the probe has a band-pass filter for the laser emitting fiber, a donut long-pass filter for the collection fibers that rejects the laser light and a two-piece lens.

Multi-spectroscopy
Probe

Raman, DRS & IFS Combined

EmVision’s multi-spectroscopy probe combines Raman, diffuse reflectance spectroscopy (DRS) and intrinsic fluorescence spectroscopy (IFS) in a single probe. The probe allows for sequential acquisition of spectra associated with Raman and IFS for two excitation wavelengths, and DRS from a broad-band white-light excitation source. DRS and IFS is in the UV/visible wavelength region, and Raman is in the near IR region. In a single probe, the benefits of applying the right spectroscopy to detect the optimal information can be realized (please see website peer reviewed article from Jun-2017 on a “Highly Accurate Detection of Cancer In Situ with Intraoperative, Label-Free, Multimodal Optical Spectroscopy”).

The Raman portion of the probe has a single laser emitting 300 µm fiber and seven 300 µm collection fibers, and the filters and lenses are arranged similar to the Raman Lensed Probe. The DRS and IFS portion of the probe uses two 300 µm fibers; either one of these fibers can be used for DRS or IFS light delivery and the other fiber being used for DRS or IFS light collection. The optical elements are permanently fixed in alignment so there is no possibility of movement.