Tempered Glass Flatness and Image Distortion Testing Machine Glass Flatness and Image Deformation Detection Instrument

Product Introduction

The tempered glass flatness and image distortion tester is the latest patented product of Lonroy. It has obtained the national utility model patent certificate, with the patent number: ZL202021001936.3. The instrument uses an optical non-contact probe to scan the surface morphology of the glass, measures the arch-shaped and wave-shaped curves of the glass and calculates the peak and valley values (PV values), optical refraction (OP values), and edge warping of the glass. Through multi-line scanning, it generates a 3D shape map of the glass surface, as well as the deformation curve and parameters of the glass in the transverse direction. The PV value is used to evaluate the flatness of the glass, and the OP value is used to evaluate the image distortion of the glass. Two statistical methods, Pareto chart and histogram, are adopted to comprehensively evaluate the flatness and image distortion of the glass.

The glass is placed vertically in front of the sample table of the equipment, with its back against the crossbar, maintaining the glass in a stationary and free from external force state. The measurement system controls the sensor to move uniformly in the horizontal direction (X-axis) to measure the displacement with the glass, gradually increasing the height of the sliding table, scanning the glass surface at different heights (Y-axis), and completing the scanning of the entire surface morphology of the glass. The following curves are obtained:

In order to analyze and calculate the size and causes of surface deformation, the curve obtained from the X-axis scanning is decomposed into two curves: the arch-shaped curve and the wave-shaped curve. The arch-shaped curve represents the overall large deformation (Overall Bow), while the wave-shaped curve represents the local small deformation, which is also known as the roll wave (Roll Wave).

As well as the corresponding optical power (OP) curve and peak-valley (PV) value curve

By using software to synthesize the 3D topography map of the glass surface. And the 3D diagram of the rollers, which is the final visual effect after flattening the arched shape.

The 3D image can be rotated up, down, left and right, which is helpful for observing the deformation of the glass. On the right side, different colors represent the refractive index values, allowing users to intuitively understand the degree of deformation of the glass.

There is also a severe arc-shaped curvature perpendicular to the direction of glass transmission. This deformation, which is often overlooked by people, is an important factor causing image distortion in the building curtain wall. The instrument has plotted the deformation curve in this direction at equal intervals, as shown in the following figure.

In the statistical results shown in the figure below, the maximum, minimum, average, median, 90% threshold, 95% threshold values of the optical aberration (OP) and peak-to-valley (PV) values for the front, middle and rear sections of the glass, as well as the edge warping of the front and rear sections of the glass, and the overall optical aberration of the glass (including the arc-shaped curvature), the roller wave optical aberration and the PV values are presented. Additionally, the Pareto charts and histograms of these statistical data are provided.

Through the Pareto chart analysis, it is possible to obtain the cumulative proportion of this piece of glass that is no greater than a certain threshold (for example, 50 mdpt) and the cumulative proportion of that which exceeds a certain threshold (such as 150 mdpt). By examining the PV value, overall optical power, and roller wave optical power, a comprehensive evaluation of the flatness and image distortion of this piece of glass can be achieved.

According to the size of the glass sample, the instrument offers two options for setting the number of scanning lines: automatic and custom. After the test is completed, a glass scanning position map can be generated, which visually reflects the locations of various deformations in the glass. As shown in the figure below.

Finally, a report on the test results is generated, which can be printed or stored.

Tempered Glass Flatness and Image Distortion Testing Machine Glass Flatness and Image Deformation Detection Instrument