"Prior art methods for measurement of coatings range from the simple to complex. Simple techniques include the emission of light of a single IR wavelength, such as 905 nm. The IR light is reflected from the coating on the sheet and is detected by an IR receiver. This technique has been successfully implemented by
"Another simple technique for detecting coatings is disclosed in U.S. Pat. No. 7,652,760 which describes a conductivity sensor for detecting the presence of certain coatings. This technique is limited by the requirement for conductivity of the coating and in its ability to discern between multiple coatings exhibiting varying conductivity.
"A complex technique for the measurement of coatings is a spectrometer. A spectrometer measures the optical response of a sheet material and of the coatings on the sheet material by measuring the transmission and reflection of light over a broad spectrum, typically 500 to 1,500 nm range at high resolution, often 1 nm or better. Spectrometers are broadly used to develop and control the application of thin film coatings on sheet material because of their ability to measure the entire reflection profile of a coating to high resolution and accuracy. A spectrometer offers high resolution and accuracy, but is slow and costly and is therefore not appropriate for coating detection in a sheet fabrication process.
"Several prior art sources use triangulation of a laser reflection from the surfaces of the sheet material to measure thickness. ISRA of
As a supplement to the background information on this patent application, VerticalNews correspondents also obtained the inventors' summary information for this patent application: "The device and method of the present invention provides for detecting a coating on a first surface or a second surface of a transparent sheet, measuring a thickness of the transparent sheet and measuring a spacing between at least two transparent sheets combines the use of triangulation with a very coarse spectrometer to provide coating and thickness from the same device. This device also makes such measurements on a moving transparent sheet in an industrial production environment without physical contact with either surface of the sheet. Light is provided by multiple light emitting diodes (LED) of multiple wavelengths, reflected off the surfaces of the glass and reflections are imaged by a two-dimensional (2D) CMOS image generating device. The reflected images from multiple LEDs off of multiple glass surfaces are measured simultaneously using the 2D image generating device. The use of a monochrome 2D image generating device and ultraviolet light, visible light and infrared light from LEDs allows simultaneous measurement of sheet thickness, coating presence, coating type and coating location.
Most Popular Stories
- Accenture Gets 8 Percent Bump in Q1
- Insurance Rule Change Angers Industry
- Revised GDP Up 4.1 Percent in 3rd Quarter
- Alex Kinsey, Sierra Deaton Crowned 'X-Factor' Champs
- Obama Opens Last-Minute Loophole in Insurance Law
- Obama's Dad Was Abusive Drunk, Half Brother Says
- Brian Boitano Announces That He Is Gay
- BlackBerry Posts $4.4 Billion Quarterly Net Loss
- The Costs of Repealing Obamacare
- Economic Growth Boosts U.S. Futures