The patented solid state sensor uses the established principle of Total Internal Reflection in a novel way to allow a linear probe to be used. Inside the probe, which is fully encapsulated, is a ladder of Infra Red LEDs and Opto-sensors which are electronically scanned by the control electronics to give a direct indication of liquid level. This is independent of dielectric constant, conductivity, temperature, pressure etc. The design is modular allowing any length of probe to be manufactured. Where required it can also be certified Intrinsically Safe. The inbuilt redundancy of data allows for self checking and automatic fault warning.

The Optical Level Sensor (OLS) has been tested and selected by a large UK supermarket chain for use in monitoring the level of liquid refrigerant. Other applications for the OLS are in the chemical, heating and ventilating, food and drink, oil, process and water industries.

Product Innovation is currently looking for distributors/installers/specifiers in the retail refrigeration market outside the UK to promote and distribute the product.

Product Innovation can make prototypes for specific applications on request. For more information contact the Chairman, Peter Frank at

Introduction to the OLS

OLS Datasheet

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