Optical and spectral sensing

optical and spectral sensing hero

Our areas of expertise include hyperspectral and multispectral sensing, biomedical optics and applied machine learning.

Hyperspectral imaging solutions

 

Hyperspectral imaging refers to the acquisition of 2D images over many discrete, narrow wavelength bands typically spanning the visible and near infrared parts of the electromagnetic spectrum. A hyperspectral camera combines the action of a spectrometer with an imaging device.

In contrast to conventional colour cameras, for which only three colours are available (red, green, blue), a hyperspectral camera provides hundreds of ‘colours’, some of which are invisible to the naked eye.

The resulting hyperspectral ‘cube’ can therefore provide a data set rich in information typically indicating the presence of certain chemical bonds or properties in the object being imaged.

Applications are numerous and span many industry sectors including agriculture, viticulture, food, wood, environmental science and medical devices.

Laser speckle imaging

 

Laser speckle is the random pattern seen in images illuminated by laser light. Dynamic changes in the speckle pattern indicate movement. Analysis of speckle patterns at a range of camera exposures allows us to quantify the dynamic properties of the pattern and to infer fluid dynamics, such as blood flow.

Laser speckle analysis proceeds in two stages. The first stage is a statistical filtering operation to derive the contrast of the speckle pattern. Fast-moving patterns, which change during the camera exposure, result in blurred image with reduced contrast. The second stage considers the contrast at different camera exposure times, from which perfusion and, in some cases, flow can be measured.

Laser speckle imaging can used to assess visual function by analysing pupil performance with and without visual aids, such as glasses.

Sensing tool box

 

We welcome enquiries from any industry sector or research institution regarding the use of our hyperspectral imaging equipment. We can offer a portable multi-spectral imaging/spectroscopic toolbox, comprising monochrome cameras with a set of optical bandpass filters, illumination with control of spectrum, intensity, triggering, etc. and a portable spectrometer or spectrometers to aid rapid design of spectral imaging solutions, including image processing software.

Case study

Measuring tree growth with spectral imaging

Trees

Business opportunity
Tree management: a system to count and measure tree growth in the field using spectral imaging.

What we did
Tested the feasibility of a camera-based approach to count and measure tree height.

Result
Developed a specification and development plan for a prototype system that can be applied in the field.