Back plate, is (back light) is the screen image in front and back plate is a manufacturer of LCD LCD. LCD liquid crystal display LCD panel does not shine, can only be pervious to light, so to be on the back and a highlight of the luminous body, this is the back plate, is really a fluorescent light with a reflector.
Back plate design principle
General principles of product design
(a) to meet customer demand for product structure and performance
Product basic structure: refers to the structure shape, have an impact on customer module assembly structure.
Due to the basic structure of product to customer module, we can not change, in addition to the client module haven't designed, only design it after being back plate out.
2. The properties include: brightness, uniformity, storage temperature, temperature of the input current, voltage and other test conditions and the requirements of the optical.
2.1 input current voltage is determined by the guest module, so when the design should clearly understand the IF and Vf value, in order to deal with brightness.
2.2 brightness refers to the strength of the brightness light-emitting OuDeGuang per unit.
As for our company now can reach 2.3 storage temperature range of - 30 ℃ ~ + 80 ℃; Action - 20 ℃ ~ + 70 ℃ temperature.
(2) of structure analysis
Design: 1. The structure geometry should ensure as far as possible is advantageous to the forming principle, avoid complicating the mould.
1.1 products can design to go insert, for example, don't walk is designed for the slider. And walking on mould slider to products will have a weld mark, influence the aesthetics of the products, for more will affect the brightness of light guide plate.
2.2 go insert hole of generally more than 1.0 mm, in order to avoid break off chip in the sliding process.
3. The wall thickness
1) the thermosetting plastic material.
The thinnest wall thickness: Tmin = 1.5 ~ 2.5 mm.
2) thermoplastic material: back plate to choose materials for such materials.
The thinnest wall thickness: Tmin = 0.25 mm, but due to the restriction of the injection molding, in 1.1 inch, product wall thickness must be at least 0.4 mm.
4. To strengthen: to avoid stress deformation, in the case of does not affect the product assembly, can add appropriately stiffener.
5. Bearing surface: in order to avoid friction caused by the wear of the textured surface as far as possible need not the entire plane.
6. The rounded: in the case of does not affect the assembly, can be appropriate to add rounded corners, to facilitate ejection.
(3) the rational size tolerance
1. A and B cover area size tolerance shall be computed according to the limit of tolerance. The upper limit of B cover should be equal to or less than the lower limit of A cover, but the upper limit of A cover is not much larger than B cover lower limit, if too many large assembly is loose, can also affect the brightness. So the plastic mould can reach the minimum tolerance should be considered a given size tolerance.
2. The dimension chain should be rationalized.