06 Sep 2002
The pick of this week's hottest patent applications in the world of photonics.
• Consumer worries about being exposed to microwave radiation when using mobile phones may soon be alleviated. Scientists at Warwick University in the UK have patented a hands-free system that makes use of an optical link between the user's phone and their ear.
The invention involves converting electrical signals from the phone into an optical signal that is guided through a plastic tube to an ear-piece. The ear-piece contains a crystal-based speaker to convert the optical signal into an audible form. Since the phone does not have to be placed near the user's head and the plastic tube cannot act as a radio antenna, the user is effectively shielded from exposure to any microwaves.
• If you're having trouble reading bad handwriting, Edward Fisher from Wisconsin, US, may have the answer. He is patenting a pen-shaped device for recording and recognizing handwritten characters or graphics.
The invention, outlined in patent application WO 02/069247, contains an image sensor, light source, light detector, force sensor and microprocessor -- all contained in a pen. Movement of the "pen" is recorded by the image sensor while the optical navigation sensor tracks features of the writing surface. The orientation of the pen to the writing surface is also analyzed.
• FastCom Technology in Switzerland has designed an image analysis system for the automatic detection of fires. The invention, deatailed in application WO 02/069292 relies on recognizing flames and or smoke by analyzing a sequence of images collected by digital cameras. Computer algorithms compare the frequency content of the images with a reference image to determine if there is any fire or smoke present.
• Reytech Corportation of the US is patenting a new type of nonlinear optical crystal made with a Beryllium Oxide (BeO2) structure (WO 02/068731). Examples of materials in the family are Na2BeO2, Li2BeO2, K2BeO2 and Cs2BeO2. Applications of the crystal include use in optical parametric oscillators.
Oliver Graydon is editor of Optics.org and Opto & Laser Europe magazine.