LiteMax LF1201 Sunlight Readable 12.1" LCD Display Preliminary Product Document Rev : Date : 0.3 Jan. 29,2000 LiteMax Electronics Inc. No.8, Lane 89, Sec. 3, Chung-yang Rd., Tucheng City, Taipei County, Taiwan R.O.C. Tel: 886-2-2267-6766 Fax: 886-2-2267-6779 Homepage: http://www.litemax.com.tw General Introduction The Lite Max model LF1201 is a 12.1" sunlight readable color TFT-LCD product. It consists of TFT LCD panel module (SP1201), LCD controller board (LCN101) and backlight inverter (LI2001). By applying the Lite Max of very high brightness (VHB) technical to the LF1201, it has a big improved quality on display. Basically, there are three major advantages for VHB application and they are described below: 1. Brightness For a traditional LCD in the market now, the brightness are measured to be around 200 ~ 350 nits under a regular sunny day. However, the brightness of LF1201 can be up to 1308 nits. A better enhancement of picture quality can be shown on the screen in the indoor or outdoor environment. 2. Viewing Angle View Angle (degree) Brightness (nits) -80 -60 -40 324.2 645.5 1135 -20 0 1317 1308 20 40 60 70 1059 465.7 144.3 96.91 From above measured data, the LF1201 has a wider viewing angle. It means the viewing angle for LF1201 is closer to 180 degree than a traditional LCD on the same brightness of viewing angle position. 3.Contrast Ratio The definition of Contrast Ratio: ON (White) luminance / OFF (Black) luminance. Luminance of LCD screen in white is Y (w) Luminance of LCD screen in black is Y (b) In the dark ambient, the LF1201 screen in white is 1308 nits and in black is 6.69 nits. Then Contrast Ratio: 1308/6.69=195.5 LiteMax Confidential 2 However, the Contrast Ratio drops significantly in the bright ambient for the real application. The reason is due to the reflections and glare at the surface of LCD. Hence, the contrast ratio should be modified as below: The Ambient Contrast Ratio: [Y (w)+Y (g)]/[Y (b)+Y (g)] Where Y (g) is the background luminance Y (g) caused by light scattering or reflection at the LCD front surface. In the bright ambient of temperature 25 degree C and indoor, the background luminance Y (g) of LF1201 is <= 10 nits, then The Min of Contrast Ratio: (1308+10)/(6.69+10)= 78.97 We know the max brightness usually is under 300 nits for a traditional LCD application. Under the same bright ambient compared with LD1201, the Min of contrast ratio of traditional LCD will be less than 30 for a real application. Hence, we can make a conclusion that LF1201 can perform a better quality image. LiteMax Confidential 3 A. LCD Panel Module (SP1201) 1. Introduction SP1201 is a 12.1", high efficiency sunlight readable LCD panel module. This module consists of Sharp LQ121S1DG11 TFT color LCD and a Lite Max very high brightness (VHB) backlight mounted onto the back of the LCD. The entire is about 24.7 mm thick and has the same footprint as the original Sharp LQ121S1DG11 LCD. The SP1201 LCD is a high contrast, wide view-angle LCD and a wider operating temperature range. In the normal mode operation, the SP1201 module delivers 1308 Cd/m (nits) LCD screen brightness at a backlight power of 23.25 Watts. With a dimming inverter, the module can be operated in a reduced brightness mode with lower power consumption and longer lamp life. In both modes, the display is highly readable under direct sunlight. In addition, the color tone of 'white' displayed on the LCD screen is closely matched to the color of normal sunlight. With a wide dimming range of Lite Max inverter, the SP1201 LCD panel module presents a surperb color image over ambient illumination levels from full bright sunshine to total darkness, making it highly suitable for various outdoor applications. LiteMax Confidential 4 2. LCD Panel Module Optical Performance The typical SP1201 LCD panel module screen luminance and contrast ratio are shown in the figures below: Brightness 1400 1200 1000 Vertical view 800 Horizontal view 600 400 200 0 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 Viewing Angle The LCD screen luminance is measured with the LCD in the 'Off' state (i.e. the pixels are not energized). This is the 'White' state with maximum luminance. Quite often, this 'Off' state is brighter than the 'White' displayed on the screen after the LCD is turned on. The difference may be caused by the graphics card and/or on the LCD controller card driving this display. When the LCD is driven properly, the luminance difference between the 'Off' state and the 'White' color should be less than 10 %. LiteMax Confidential 5 Contrast Ratio 250 200 Horizontal view 150 Vertical view 100 50 0 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 Viewing Angle The inherent contrast ratio (CR) of the LCD is the luminance ratio between the 'White' and the 'Black' states measured in a dark room. In outdoor environments, the contrast ratio of the display drops significantly due to the surface reflections and glare caused by the ambient illumination at the front surface of the LCD and other surfaces such as touch screen or the protective window. LiteMax Confidential 6 3. Characteristics Parameters Value Units LCD Screen Luminance 1308 Cd/m White (LCD in off state) Luminance Uniformity 20% or better LCD Contrast Ratio 195.5 78.96(Min) Screen Dimming Ratio 200:1 Condition Note 2 White vs Black with 10 nits background Y(g) With LI2001 inverter LCD Screen Chromaticity White ( LCD in off state ) x=0.3430, y=0.3701 Measured at normal direction Red x=0.5946, y=0.3518 Measured at normal direction Green x=0.3141, y=0.5798 Measured at normal direction Blue x=0.1550, y=0.1529 Measured at normal direction Viewing Angle 3:00 to 9:00 direction -80 ~ 45 degrees Contrast Ration >=10 6:00 to 12:00 direction -50 ~ 45 degrees Contrast Ration >=10 3:00 to 9:00 direction -80 ~ 70 degrees Screen luminance >= 100 nits 6:00 to 12:00 direction -80 ~ 80 degrees Screen luminance >= 100nits Backlight Power Consumption 23.25 LCD Module Weight Number of CCFLs Watts Excluding inverter losses Grams with encasing 8 Note 1: All data are measured at 25- C 2 C ambient temperature. Note 2: Uniformity = (Lmax - Lmin)/(Lmax - Lmin). Lmax (Lmin) is the maximum (mininum) luminance measured with a 10 mm diameter meter aperture over the LCD active area except the last 10 mm area from the edge. 3. Optical specification, Signal Timing Specification and Signal Timing Wave Form In addition to the data described on characteristic, please refer to Sharp LQ121S1DG11 for other information. LiteMax Confidential 7 4. Interface connection 5.1 Electrical Interface Connection Please refer to Sharp LQ121S1DG11. 5.2 Backlight Lamp Connections The very high brightness (VHB) backlight in the SP1201 module uses a total of 8 cold cathode fluorescent lamps to achieve the required luminance. The lamps are electrically connected in two separate groups. Group 1 contains lamps #1, #2, #3, #4 and Group 2 contains lamps #5, #6, #7, #8. The lamps are oriented in the horizontal direction with the #1 lamp at the topside of the LCD. The lead wires connecting the lamps are terminated with two 11-pins connectors. The following are the connector pin out assignments. Pin # Group 1 Connector Group 2 Connector 1 NC NC 2 NC NC 3 Lamp#1 Lamp#5 4 NC NC 5 Lamp#2 Lamp#6 6 NC NC 7 Lamp#3 Lamp#7 8 NC NC 9 Lamp#4 Lamp#8 10 NC NC 11 Common Common LiteMax Confidential 8 6. Backlight Lamp Driving Specification It is recommended to use an inverter with a 1200 to 1300 Vrms starting voltage to run the VHB backlight in the SP1201 LCD panel module. At the maximum LCD screen luminance, the lamp voltage and current are listed below: Operating Voltage 470 Vrms Lamp Current **** mArms At this driving condition, the backlight delivers the specified maximum LCD screen brightness with power consumption about 23.25 Watts. Since most inverters used to driver CCFLs have efficiency between 75 % - 80 %, the total DC power input to the inverter is about 31 Watts. When the backlight is dimmed down, the power consumption decreases. LiteMax Confidential 9 7. Mechanical Characteristics LiteMax Confidential 10 B. LiteMax LI2001 inverter 1. Introduction LI2001 is a CCFL inverter to operate Lite Max very high brightness (VHB) backlights includes the sunlight readable LCD modules. The inverter has an on-board pulse width modulation (PWM) dimming circuit for extremely wide range luminance adjustment. Over the entire dimming range, there is no noticeable lamp flickering and the uniformity of the backlight is well maintained. When using LI2001 with LiteMax sunlight readable LCD modules, it is not necessary to synchronize the PWM circuit to vertical sync signal of the LCD. 2. Dimming Control The LI2001 accepts a 0-5V analog voltage for dimming control. It has a pulse width modulation (PWM) dimming circuit for luminance adjustment. As the dimming voltage Vd decrease from +5V, the lamp current waveform is pulse width modulated at a repetition rate high enough to prevent LCD flicker. Within each PWM, the lamps in the backlight are turned fully 'ON' for a fraction of the cycle time. The human eyes, being very slow with respect to the PWM rate, respond to the average light produced over the PWM cycle. As a result, the luminance of the backlight and/or the LCD screen is approximately to the duty cycle of the PWM waveform. The lamp current waveform with the PWM circuit Set at less than 100% LiteMax Confidential 11 In general, inverters with PWM dimming have a very wide luminance adjustment range. For most practical cases, the LI2001 inverter can achieve a dimming ratio up to 200:1. Hence, the luminance of the backlight or LCD screen can be adjusted from 100% to 0.5%. The 0- 5V dimming voltage can be generated simply by a potentiometer, by a digitally controlled UP/DOWN counter or a digital potentiometer. The inverter provides a regulated +5V supply to power the dimming circuit. However, the maximum current drain from this source should be kept less than 5 mA. At a Vd input about 0.34V and less, the duty cycle of the PWM waveform is 0% and thus, the lamps are 'OFF'. In order to fully utilize the available dimming voltage, Vd should be biased to about 0.32V and then ramping up to 5.0V. 3. Electrical Characteristics The LI2001 inverter operates at 12V DC input and can drive up to 8 lamps for a maximum output power about 22 Watts. In addition, the inverter has a regulated +5V output serving as a voltage source for the dimming control circuit. Electrical Characteristics Parameters Min Typ Max Input Vpltage (Vin) 11.5 12 12.5 Input current (I) 2.3 Lamp Starting Voltage (Vst) Frequency (f) Units Vin=12, Vd=5 V 1300 50 ON/OFF Control -OFF -ON Conditions Vrms Vin=12, Vd=5 V 53 58 0 0.2 Khz Floating Dimming Voltage(Vd) @ 100% Duty Cycle 4.9 @ 0% Duty Cycle 0.3 0.34 5V Output (+5VOUT) 4.85 5 5V Output Source Current LiteMax Confidential 5 5.3 5 12 Vdc Max brightness Vdc Zero brightness Vdc 11.5<Vin<12.5V Ab so lu te M axim u m R atin g P a ra m e te rs In ve rte r In p u t V o lta g e (V in ) O p e ra tin g T e m p e ra tu re R a n g e S to ra g e T e m p e ra tu re R a n g e M in M ax U n its 11 13 Vdc 0 50 C -2 0 80 C 4. Interface Connector Input Connector ( CN1) Pin# 1 2 3 4 5 6 7 Function 5V Output 12V Input 12V Input Dimming Control Ground Ground ON/OFF Control Output Connector (CN2 & CN3) PIN # 3, 5, 7, 9 LiteMax Confidential Function Lamp Connections 11 Lamp Common 1,2,4,6,8,10 No connection 13 5. Mechanical Characteristics LiteMax Electronics Inc. reserves the right to make changes to this document and the product which it describes without notice. LiteMax Electronics Inc. also shall not be liable for technical or editorial errors or omissions made herein; nor for incidental or consequential damages resulting from the furnishing, performance, or use of this product. In addition, LiteMax Electronics Inc. takes no responsibility for damage caused by improper use of this product which does not meet the conditions for use specified in this specification sheet. LiteMax Confidential 14