Point-Spectrum Thickness & Height Difference Inspection for Plastic Parts

I. Project Background

Plastic parts are widely used in home appliances, automobiles, electronic products and other fields. They feature lightweight and easy processing. To ensure the assembly quality of finished products, the accuracy of dimensions such as thickness and height difference of plastic parts is critical.

Therefore, manufacturers need to measure the dimensions of plastic parts during production to reduce the generation of defective products. In this issue, ShenSir uses a confocal chromatic displacement sensor to inspect the thickness and height difference of plastic parts. Let’s take a look.

II. Inspection Requirements

• Product Name: Plastic Parts

• Measurement Items: Thickness; Height Difference

• Accuracy Requirement: Dynamic repeatability of thickness and height difference within 0.005 mm

Figure | Physical Picture

III. Measurement Process

Thickness Measurement：Set measurement points on the plastic part, and measure the thickness using two point-spectrum sensors in upper-lower through-beam arrangement.

Figure | Thickness Measurement Scene

Measurement Result：10 dynamic measurements using SC04025 show thickness repeatability of 0.0005 mm.

Height Difference Measurement：The height difference is obtained by subtracting the height value of the set reference point from the height value of the set measurement point.

Figure | Height Difference Measurement Scene

Measurement Result：10 dynamic measurements using SC04025 show height difference repeatability of 0.0006 mm.

IV. Sensor Selection

• Point-Spectrum Model: SC04025Spot

• Size: 12 μm / 40.3 μm

• Measurement Range: 4 mm

• Angular Characteristics: ±25°

• Numerical Aperture: 0.423

• Working Distance: 16 mm

• Axial Resolution: 0.006 μm

• Linearity: ±0.01% F.S.

Shenshi Intelligent confocal chromatic displacement sensors support a maximum specular reflection detection angle of up to ±60°, which can effectively reduce measurement blind spots and achieve high-precision measurement of specular surfaces, high-transparency materials, liquids and multi-reflection objects. Customers with relevant needs are welcome to inquire and purchase.