The LI200 Ecutimeter is designed to analyse the reflectance of poultry egg shells.
Key system components are as follows:
- Light source
- Light path assembly
- Sample chamber
- System software
Details of System Components
Detector / Analyser
Ocean Optics Flame Spectrometer (http://oceanoptics.com/product/flame-spectrometer/)
CCD based Fiber optic coupled spectrometer. Detection optimized for the visible spectrum from 350-800nm. The system includes a Sony ILX511B linear silicon CCD array capable of a dynamic range of 8.5 x 10^7.
Ocean Optics HL2000-LL Light source (http://oceanoptics.com/product/hl-2000-family/)
Halogen lamp light source covering the visible spectrum with a long life enhanced bulb with a typical lifetime of 10,000hrs with <0.3% optical drift per hour. The output spectrum, provided by Ocean Optics, is shown.
Light path assembly
A bespoke optical fibre-based reflection probe consisting abundle of six 200 µm core optical fibres provides illumination to the sample. A further fibre captures reflected light to guide it to the spectrometer. All fibres have a numerical aperture of 0.22.
Sample chamber / holder
The sample holder is contained within a black-lined enclosed lid to allow dark (background) measurements to be performed whilst the unit is under ambient conditions. The holder is removable for cleaning and to allow replacement for customer–specific requirements.
The egg holder assembly allows simple placement of an egg for an accurate reliable single point measurement on its equator maintaining the egg – reflectance probe distance of 2mm. The sample holder is designed so that the lid does not have to be closed during measurements of either the standard or a sample (egg).
The main cabinet houses all of the major components in secure fixings ensuring optimal system performance is always maintained. Heat produced by the lamp and control hardware is rapidly dissipated from the unit via an exhaust fan. All external surfaces are suitable to be wiped down with detergents for cleaning to allow the unit to be used in sensitive areas such as farms.
The Ecutimeter software is an integrated package which performs data point selection for focus on desired wavelengths, reflectance calculations, absorbance conversions. Owing to the wide range of reflectance observed for samples such as eggs, the conversion to absorbance provides a more accurate measure of difference between samples.
For reflectance measurements, a reflectance standard and dark measurement are first performed. All raw data are stored for future analysis along with a data report for desired wavelengths of focus. Selected data can be output via Ethernet or USB to an external device / system. The system is capable of measuring and storing data for batches of 500 eggs before a recalibration is prompted by the software, to ensure consistent results. The system is pre-configured for the default settings deemed most appropriate for the measurement system, with more detailed control of settings such as boxcar averaging made available through a settings panel.
Users control the system via an integrated touchscreen; alternately external control devices can be connected via the USB interface.
The software can be customised to user needs with further calculations, such as colour measurement being possible owing to the wide spectral measurements performed. Such features can be provided via software updates, which can be performed by users in the field.
Speed of measurement
The measurement time of the system will be automatically optimized to the current state of the standard used and output of the light source. When lamp output falls below a pre-determined threshold, the system will alert the user to the need for bulb replacement.
Typical time per measurement is ~30ms. The system will be capable of measuring batches of 500 eggs before standard recalibration is prompted to ensure measurement consistency. With manual placement a rate of ~800 eggs per hour for a single point per egg is possible.
Sample Data input
Sample data can be input via the integrated touchscreen or keyboard, alternately through an optional barcode scanner.
Sample Data output
Data can be transferred through either Ethernet or USB interfaces, either to an external system or to a storage device.
The tip of the fibre reflection probe is protected by an anti-reflective glass window. Removal of the sample holder allows access to this window for cleaning with ethanol. This should be performed should the dark count be above a pre-determined level, as alerted to the user by the software, or contamination be observed.
The rubber alignment ring for egg placement should be cleaned on appearance of contamination to maintain system performance. The alignment ring should be replaced on any sign of damage.
The LI200 Ecutimeter system is covered by Lomond Instruments warranty, details of which can be found at www.LomondInstrument.com/LI200waranty.htm