Image Credit: michaeljung/shutterstock.com
Nicéphore Niépce is widely attributed as being the inventor of photography, but he may not have envisioned how far camera technology would advance. Printable image sensors are one such development that has offered manufacturers huge benefits in flexibility, scalability and cost.
An image sensor is a key component of a camera and is used for converting an optical image into an electronic signal.
A camera’s resolution, light sensitivity, ability to track images in motion without any distortion and image quality are all based on the image sensor chip within the camera.
ISORG, a leading manufacturer of image sensors and photodetectors in printed electronics, along with global organic thin-film transistor giant Plastic Logic, developed the world’s first flexible organic image sensor that has the potential to optimize several optical design parameters of digital imaging.
Printed Image Sensors
The flexible image sensor was developed by depositing organic printed photodetectors developed by ISORG on to a plastic organic thin-film transistor backplane from Plastic Logic. The flexible sensor was found to have a resolution of 94 pixels x 95 pixels, 375 µm pitch, pixel size of 175 µm with 200 µm spacing and 4 cm x 4 cm active area.
Significance of Printed Image Sensors
According to researchers, one exciting feature of flexible image sensors is that it offers the ability to be easily scaled in to larger areas and high pixel densities. The flexible backplane technology can also be used in high performance sensor arrays where the pixels can be used to store charge created by a photo-detector layer. The charge can then be read row by row to display the image.
Another major advantage of the flexible image sensor is the organic photodetector layer. The layer has a very high absorption coefficient, which enables photo detection on the entire surface for a 100% pixel fill factor. The spectral range of the organic photodetector is very broad which means imaging systems can use the same photodetector for sensing visible and near-IR light. In addition, the photodectector can be used for X-ray sensing by adding an appropriate scintillation layer.
Image Credits: ISORG and Plastic Logic
The organic photodetector layer and the backplane are manufactured using printing methods under ambient conditions thereby reducing the manufacturing costs when compared with conventional manufacturing techniques of inorganic components. The flexible sensor allows for the utilization of PET substrates instead of high temperature substrate alternatives.
Organic electronic materials have now achieved new performance levels by meeting or exceeding the performance of equivalent inorganic electronic materials. As a result, they are currently being employed extensively on an industrial scale for manufacturing flexible displays.
Flexible printed image sensors represent a significant breakthrough in the manufacture of large area image sensors using organic materials and unique flexible transistor technology.
Researchers hope that these novel sensors will provide opportunities for a new range of applications, including sensors for mobile commerce, security and biomedical diagnostics, smart packaging sensors, fingerprint scanning identification and interactive 3D user interfaces.