In our day-to-day life, we often come across with several items or products that have their thickness measurement mentioned, such as 0.3 to 60 μm thickness of a single-layer film, bond paper with 0.17mm thickness, or 1mm of gap distance between the LCD and the touch screen, etc. If you work in a mobile-manufacturing company, you might have heard your manager suggesting for keeping at least 1 mm of distance between touch screen and LCD. In fact, conducting accurate thickness measurement is an essential part to ensure quality of a product, be it a piece of bond paper, plastic bottle, container, LCD and touch screen, or films, etc.
Have you ever thought how the dimension of the thickness is measured? Or what type of thickness measuring instrument is used to ensure the thickness of paint, or the distance between the closest opposite surfaces or the thickness of plywood, etc.? Don’t worry, if you haven’t.
Thickness measuring is the talk of this article. Go ahead and get a full insight into it.
Plywood is a great example of edge thickness. To measure the thickness of plywood, standard machine vision caliper tool is used. This instrument measures edge-to-edge distance (thickness) of plywood.
Optical interference is normally used to measure transparent coating thickness. Light waves are reflected from the top and bottom of the coating interfere. Experts observe the waves and notice whether it appears lighter or darker. The appearance of waves depends on their length, the coating thickness and the object’s refraction. The aim is to count the fringes and compare the phase & contrast of fringes. Depending on the counting result, thickness of a coasting is measured.
To measure opaque coatings, experts subtract the height of the object before coating and the height of the object after coating. Height is a measure of vertical (normal) distance. It is measured from the object surface to a reference plane. The correctness of measurement is solely dependent on the sensor, on how well the subsequent and substrate coatings line up, and on having the substrate on the same flat surface before and after coating.
Film Thickness or Measuring Small Spots
Small spots are measured using a microscope, which is easy to move. The microscope has the ability to measure 2μm to 100μm depending on objective. It is the right thickness measuring instrument measure film. It is also known as thin-film measurement tool.