Application of Black-and-White Densitometer in Measuring the Light Transmittance of Film Panels

Application of Black-and-White Densitometer in Measuring the Light Transmittance of Film Panels

Film panels are plastic products made from flexible plastic materials such as PVC, PC, and PET. Graphics, text, and logos are integrated onto them using screen printing technology. They are equipped with strong double-sided adhesive and are used for labeling or protective purposes. The material used for the film panel determines its price and performance.

Film panels feature clear and intuitive graphics and text, and can adapt to different flat and curved surfaces. With advantages like an attractive appearance, comfortable feel, convenient assembly, stable quality, long service life, low cost, and good waterproof/fireproof/oil-resistant properties, they are poised to rapidly replace traditional mechanical switches. They are widely used in household appliances, office equipment, instruments and meters, automotive instrument cluster display panels, electromechanical products, industrial controls, toys, and other finished products.

Product Sample

We received a customer sample: an automotive instrument cluster display panel. The instrument cluster is a critical reference for drivers while operating the vehicle. By viewing the various data readings and indicator lights on the panel, the driver can clearly understand the vehicle's driving status and engine operation, enabling accurate driving, improved safety, and timely detection and resolution of potential faults. Automotive instrument clusters are generally located directly behind the steering wheel and consist of components like the speedometer, fuel gauge, odometer, temperature gauge, seat belt warning light, door open indicator, high beam indicator, and low beam indicator.

Hollowed-out lines are set on a base black film layer. When illuminated by a light source, these hollowed-out lines become the light-transmitting areas. Light passing through these lines displays icons, dials, numbers, and letters, enabling the instrument cluster's indicating functions. An enhanced black film layer is applied over the base black film layer. This enhances the opacity of non-display areas, improving the uniformity and clarity of graphics, text, and scale displays. A key factor in controlling product quality is meeting the requirements for the light transmittance of light-colored inks, colored inks, and dark inks.

Introduction to Black-and-White Densitometer

An optical transmission black-and-white densitometer is an instrument for measuring optical density. YUSHI Digital Black-and-White Transmission Densitometer is used to measure the amount of light transmitted through a test sample to determine the amount of light absorbed by its surface. It mainly consists of an illumination system, a light collection and measurement system, and a signal processing system. It uses an AC modulated light source to provide a stable, high-quality light beam. The light signal transmitted through the sample is converted into an electrical signal. After processing, this signal is sent to a microcontroller, and finally, the blackness value (related to transmittance and density) of the sample is displayed.

Test Results

The method described above is highly suitable for measuring the light transmittance of translucent materials and film-type materials. This includes PC membrane switch overlays, PVC acrylic control panels, PET membrane keypads, and similar materials used in the electrical appliance, industrial, and instrument manufacturing industries.