Abstract — Manufacturers of multi-layer films can realize significant cost savings, product quality improvements, and reduce the risk of product failures by accurately measuring individual layer thicknesses of multi-layer materials instead of relying on gauging that can only provide total thickness.
On June 26th, 2018, Lumetrics was awarded a new patent for “Associated Interferometers Using Multi-Fiber Delay Lines.” An interferometer apparatus which include two or more coupled fiber optic Michelson interferometers using fiber optic stretches which stretch two or more optical fibers wound around the perimeter of the optical fiber stretchers by the same amount is disclosed. Preferably a pair of reference and sample fiber optic stretches are utilized which run in a push-pull mode of operation. When one of the interferometers is a coherent light interferometer it can be used as a reference distance scale for all of the remaining low coherence light interferometer. A method for measuring a physical property of a device under test is also disclosed using the apparatus of the present invention. This patent allows the user to measure optical thickness at multiple locations on a sample or in a manufacturing line simultaneously with a single measuring instrument without the need of an optical switch. This enables faster measurement and continuous measurement capability 100% of the time.
filed under: interferometry
The windshield has become an increasingly complex component of an automobile requiring the latest metrology tools to meet the demands of the world’s leading automotive manufacturers. While limited to more expense vehicles today, Heads Up Display’s (HUD) will continue to increase in popularity as they help drivers focus on driving.
Lumetrics was granted a patent allowance for the technology used to measure a contact lens using the ClearWave™ plus. This patent allowance works in tandem with two previous patent filings that Lumetrics was awarded concerning the apparatus of measurement.
The ClearWave Plus uses a modified ClearWave in combination with the industry standard OptiGauge® thickness measurement system. This provides contact lens manufacturers center thickness (CT), Sagittal Height (SAG), diameter, radius of curvature, and all the wavefront measurements that currently require three separate systems to obtain.
The OptiGauge II is a highly accurate instrument for non-contact light-based thickness measurements of transparent and translucent materials. The instrument is subject to a low measurement limit of 12 microns (for glass). It means that only layers that are above this limit in thickness can be measured accurately to a precision of 0.1 microns. However, in some instances, it is possible to measure thicknesses that are below this limit. For example, it can be done when thin coatings or adhesives are applied to thicker substrates.
filed under: Non contact thickness measurement
A small degree of wedge angle has been found useful in minimizing ghosting in automotive windshields with Heads Up Displays (HUD). The Lumetrics OptiGauge II can measure the thickness of all layers of a laminated windshield simultaneously and is capable of determining the wedge angle as a function of location on the windshield with a high degree of accuracy as well as determining how much wedge is in each layer.
Abstract — Lumetrics has developed a method to monitor the temperature of a fluid by measuring changes in its refractive index. The demonstrated approach can be adapted for online applications to monitor the temperature of fluids in real-time and in a completely non-invasive manner.
filed under: non contact temperature monitoring
Abstract— Lumetrics has developed a fixture that expands precision measurement capabilities of the commercialized low-coherence interferometer, OptiGauge II, to materials that are not translucent to its measurement beam light of 1310nm. The fixture contains two probes oriented towards each other and an optical reference surface. The effects of the temperature on the measurement accuracy are eliminated via a calibration procedure conducted before the measurement.
Abstract — High quality glass tubing production relies on tightly controlled manufacturing processes. With the addition of a Reference Signal Generator (RSG), the OptiGauge II can aid the control of the straightness of the tube by measuring its bow.