capacitive touch screen Cosmetic spec
summary
Regardless of capacitive touch screen or resistive touch screen, the inspection standards for product appearance are similar. If the general standard cannot meet your needs, you can negotiate to use stricter standards, but this means lower yield rate and higher price.
1.Method and environment for capacitive touch screen and resistive touch screen inspection
2.Common defects pictures of touch screen
3.Definition of touch screen detection position
4. Standard of touch screen active area
Capacitive touch screens are widely used in many fields because of their excellent performance. The capacitive touch screen supports multi-touch and has high sensitivity. Ideal for consumer electronics such as smartphones, tablets, and laptops. The capacitive touch screen not only has high sensitivity, but also has excellent durability and ease of use. With different protective covers, the durability of the capacitive touch screen will be greatly improved. Different designs can also achieve waterproof and glove touch effects. Suitable for applications in control panels, medical equipment and ATMs.
So, when you choose and use a capacitive touch screen, how do you need to detect a capacitive touch screen? Like the lcd cosmetic spec of the tft display, the touch screen also has a cosmetic spec. The following is the detection method for your. reference:
Purpose In order to ensure product quality requirements, prevent defective products from flowing into the hands of customers, and meet customer requirements to the greatest extent, standardize the production processes of our company’s capacitive screens and the appearance inspection of shipments.
- Scope of application
2.1 Capacitive screen IPQC process appearance inspection.
2.2 Capacitive screen QA appearance inspection and shipment appearance inspection.
2.3 Internal production appearance inspection of capacitive screen production department.
- Inspection basis
3.1 Sample approval letter and limited sample.
3.2 Customer special requirements.
- Inspection conditions
4.1 Temperature: 25±5℃;
4.2 Humidity: 60±10%RH.
4.3 Lighting brightness: within 800~1200 lux (under cool white fluorescent lamp of 12-30W);
4.4 Inspectors must wear dust-free finger cots during inspection.
- Use tools
5.1 Dimensional inspection: calipers, micrometers.
5.2 Point and line defects: film ruler, two-dimensional.
5.3 Edge chipping, missing corners, and crack defects: 10 times or more visual mirror, CCD magnifying glass.
- Inspection method
The distance between the inspected product and the light source is about 50CM, and the inspector’s vision is above 1.0 (or corrected vision), and the position of 20-30cm away from the inspected product is visually inspected with reflected light, and a black cardboard is placed under the product as a background. The product inspection time is 10 seconds. Schematic diagram of inspection operation:
- Definition
Point-line defects (white spots, bubbles, concave-convex points, stains, scratches, and wool) are considered linear defects if the length of the defect is more than 2.5 times the width, and the point size and diameter are calculated as: D = (X+Y)/2 (X, Y are point maximum and minimum diameters).
Common defects pictures on touch screen
dots defects
stain
hole defects
scratch
bubble defects
damaged
Cosmetic spec
The defects appearance of the capacitive touch screen mainly occurs on the cover glass, which is divided into AA display area and ink area. The complex cover plate also has camera holes, AR holes and camera holes, etc.
| Area | Defect item | Inspection standard | |
| AA area | dot defect | white spots, bubbles, Bump point | ①D≤0.10mm, the number is not counted, Not block; ②0.10mm＜D≤0.15mm, If the distance between two points is greater than 10mm, 3 points are allowed; ③0.15mm＜D≤0.2mm, Only 2 points are allowed to be received ④D>0.2mm, not accepted. |
| crystal point | ①D≤0.05mm, 3 points are allowed, and the distance between the two points should be large at 10mm; ②0.05mm<D≤0.1mm, distance greater than 10mm is allowed There may be 2 points; ③0.1mm<D≤0.15mm, only one point is allowed to be received; ④ D>0.15mm, do not accept. | ||
| rainbow dot | Press the back of the point with your hand, the size and color of the front eye-level point Color, colorless point according to the white point standard, light color point according to the crystal point mark Accurate, dark points are judged according to the black point standard. | ||
| other same color point | The light color points are processed according to the crystal point standard, and the dark color points are processed according to the black point standard. Make a judgment. | ||
| linear defect | wool, scratches | ①Length ≤ 1mm, width ≤ 0.03mm, the number of strips is not counted, but two The bar spacing should be greater than 10mm; ② 1 mm < length ≤ 2 mm, width ≤ 0.03 mm are allowed to have 2 pieces. But the distance between the two should be greater than 10mm; ③2mm<length≤3mm, width≤0.03m, one piece is allowed; ④Length > 3mm, width > 0.03mm, if any item exceeds the limit, do not connect receive. | |
| Linear ink | ①Length ≤ 1mm, width ≤ 0.03mm, 3 pieces are allowed, But the distance between the two should be greater than 10mm; ②Length ≤ 1mm, width ≤ 0.05mm, 2 pieces are allowed, But the distance between the two should be greater than 10mm; ③Length > 1mm, width > 0.05mm, any item exceeding that will not be accepted. | ||
| Fingerprints, dirt, etc. | ①D≤0.1mm, two places are allowed, but the distance between the two places should be greater than 10mm;②0.1mm<D≤0.2mm, one place is allowed; ③D>0.2mm, not acceptable. | ||
| Flatness | Under 20W cool white industrial light, there should be no obvious dents and bumps on the surface. | ||
| Area | Defect item | Inspection standard | |
| ink area | white spots, bubbles, Bump point | ①D<0.10mm, 3 are allowed, but the distance is greater than 10mm; ②0.1mm≤D≤0.20mm, two points are allowed, but The distance should be greater than 10mm; ③D>0.25mm, do not accept. | |
| scratches | ①Length<1mm, width<0.05mm, the number of strips is not counted, but two The spacing should be greater than 10mm; ②1mm≤length≤2mm, width≤0.05mm, 2 pieces are allowed. But the distance between the two should be greater than 10mm; ③2mm≤length≤3mm, width≤0.05mm, one piece is allowed; ④Length > 3mm, width > 0.05mm, any item exceeding that will not be accepted. | ||
| Fingerprints, dirt, etc. | 0.1mm<D<0.2mm 2 places are allowed, but the distance between the two places should be greater than 10mm. | ||
| Translucent | Light penetration is not allowed. | ||
| chipped edge | X≤0.3mm, Y≤0.3mm, Z<thickness. 2 are allowed, but The distance between the two should be greater than 10mm. X, Y, Z arbitrarily exceed the given Values are not accepted. | ||
| crack | Not allowed. | ||
| Fingerprints, dirt, etc. | ①D≤0.1mm, two places are allowed, but the distance between the two places should be greater than 10mm; ②0.1mm<D≤0.2mm, one place is allowed; ③D>0.2mm, not acceptable. | ||
| Flatness | Under 20W cool white industrial light, there should be no obvious dents and bumps on the surface. | ||
Customization for special requirements
Although there are common detection standards in the industry, when you do not ask a question, this standard will be implemented by default. If the product you design has high requirements and requires special procedures, Hexie Optoelectronics is willing to work with you to complete all this. Welcome to discuss your ideas with us!
