按键背光介绍与设计

Slim Backlit
Design Process SPEC & Backlit Test Backlit Specific Issue
LED firing Type
Reduce LED pitch
Reduce dark zone
LED firing Type
LED Emitting Position :
corner legend can have the same brightness.
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Light leakage
Mask Design 2
center legend corner legend
Masking
In order to solve light leakage, limpid areas of masking mylar become smaller and only cover half corner legend. This will cause corner icon become darker when lighting.
基本名词
Min. Luminance
Max. Luminance
Uni.(%) = 100* Min. Luminance/Max. Luminance
Agenda
Backlit Module Introduction
LED firing Type Backlit Assembly Light leakage, 开胶 Backlit Production Process
SE4 Sample for Backlit Rotate luminance Analysis
SE4 normal condition
Max：23.27 nits
Min：8.12 nits
Uni：34.89%
SE4 rotate condition (x=0.8mm, y=0.8mm)
Max：21.87 nits Min：6.10 nits Uni：27.90%
Non-low-cost backlit
Special Case 1
AgendaБайду номын сангаас
Backlit Module Introduction
LED firing Type Backlit Assembly Light leakage, 开胶 Backlit Production Process
Backlit 介绍 及设计需注意重点
8/23, 2012
Agenda
Backlit Module Introduction
LED firing Type Backlit Assembly Light leakage, 开胶, ESD Backlit Production Process
(Ref Hole
typ-Support
Hole
typ)+
(Ref Hole Tolerance
upper
- Support Boss Tolerance lower)+
upper)+ lower)
(Support Boss Center Tolerance (Ref Outline Tolerance
So we just consider reflector assembly with keyboard.
Design concept: Reflector hole radius is bigger 0.1mm than Support boss radius
Keyboard & Backlit Assembly
Backlit Keyboard Stacking- Darfon Patent (Vito,2001/11/30,6860612)
Backlit Module KB Module
Masking
LGP Reflector
LED&FPC
Backlit Module Introduction
Backlit Module Parts List
Slim Backlit
Design Process SPEC & Backlit Test Backlit Specific Issue
Backlit Assembly
Circle, main locate hole
Ellipse Hole Tolerance is +-0.05mm Hole Center Tolerance is +-0.1mm
Slim Backlit
Design Process SPEC & Backlit Test Backlit Specific Issue
Light leakage
Mask Design 1
center legend corner legend
Masking
Masking mylar doesn’t cover the keycap corner legend. Center legend and
In (x=0.8mm, y=0.8mm) rotate condition, SDA sample luminance is still in Spec (min=3nits, Uni=18%).
Agenda
Backlit Module Introduction
LED firing Type Backlit Assembly Light leakage, 开胶 Backlit Production Process
1. When backlit parts’ holes dimensions are on upperlimit and backlit parts are assembled lean on the same side. Backlit’s hole is D3.8mm.
The worst assembly condition will be happen.
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Light leakage
Mask Design 2
center legend corner legend 1. Corner icon is darker than center icon because corner icon is covered by masking. Corner icon can’t have good uniform brightness. Up-side brightness is brighter than down-side brightness because downside of corner legend is covered by masking.
upper
- Support Outline Tolerance
=0.1+(0.05+0.05)+(0.1)+(0.1+0.15)=0.55mm
Reflector exceed support 0.55mm
SDC Sample for Backlit Rotate luminance Analysis
TIR
Backlit Module Introduction
Backlit Module Working Principle2
Backlit Module Introduction
JP与US下方的印刷区有明显的不同，外观即可看得出来
Backlit Module Introduction
在Masking 空白处加印大字体的版本区分
Reflector tolerance
Reflector hole tolerance is +-0.05mm Reflector hole center tolerance is +-0.1mm Reflector outline tolerance is +-0.1mm
Support tolerance
Keyboard & Backlit Assembly
Reflector Dimension
As above mention, when backlit parts’ holes dimensions are on upper-limit (R1.9mm), and backlit parts are assembled lean on the same side. The worst assembly with keyboard will be happen.
Slim Backlit
Design Process SPEC & Backlit Test Backlit Specific Issue
Backlit Module Introduction
Backlit Keyboard
Backlit Module
Backlit Module Introduction
Hole Tolerance is +-0.05mm
Backlit parts’ holes dimension are the same Jig main locate pin dimension is R1.75mm(D3.5mm)
Backlit Assembly
When backlit parts’ holes dimensions are on upper-limit (R1.9mm), and backlit parts are assembled lean on the same side. The worst assembly with keyboard will be happen.
2. When backlit parts’ holes dimensions are on upper-limit but backlit parts are assembled lean on different side. The worst assembly condition won’t be happen, because jig pin will restrict backlit’s hole to D3.5mm (equal to jig pin dimension)
Support Boss tolerance is +-0.05mm Support Boss center tolerance is +-0.1mm Support outline tolerance is +-0.15mm
Keyboard & Backlit Assembly
Total Assembly Tolerance (one direction)
SDC normal condition
Max：19.14 nits
Min： 7.91 nits
Uni：41.33%
SDC rotate condition (x=0.8mm, y=0.8mm)
Max：17.24 nits Min：6.18 nits Uni：35.86%
In (x=0.8mm, y=0.8mm) rotate condition, SDA sample luminance is still in Spec (min=3nits, Uni=18%).
LED下侧发光 LED侧发光
Side Emitting
• Higher Uniformity (30% Up) • Lower Cost (FPC+LED) • Design Easily (易标准化,无死角)
LED firing Type
Review 2009: 下侧发光侧发光
Ten-Key Backlit
料号叙述
语文版本
Backlit Module Introduction
1. 不同语文别的LGP，其LGP上的离型膜会有不样的颜色 2. Backlit module出货前，皆会进行测光，不同语文别由于布点 的layout不同，如果混到LGP，测光会Fail。
Backlit Module Introduction
LGP Masking
LED&FPC
Reflector
Backlit Module Introduction
Backlit Module Working Principle
1. FPC&LED：Light source and circuit 2. LGP (Light Guide Plate) : Guide light material 3. Reflector：Re-use the light loss from LGP 4. Masking： Prevent light-leakage at non-lighting area