Samsung Display Co., Ltd.

Samsung Electronics Co., Ltd.

Samsung Displayco., Ltd.

Min-Soo Choi

Won-Sik Oh

Hwanwoong Lee

Moon-Shik Kang

Taegon Im

Myoung-Soo Kim

Jin-won Jang

Youngsup Kwon

Eun Chul Shin

Seung-Wan Kim

Hwan-Woong Lee

Dae-Sik Lee

Won Sik Oh

Song-Yi Han

Seung-Young Choi

Jae-Eun Um

Min-Gyu Kim

Young-Sup Kwon

Tae-Gon Im

Gwang-Teak Lee

Jin-Woo Park

Tae-hyung Kim

Kyunho Kim

Yun-Gun Lee

Tatsuhisa Shimura

Osamu Sengoku

Jin-Taek Hong

Young-Suk Ha

SeungYoung Choi

Wee-Joon Jeong

Gwangteak Lee

Young Sup Kwon

Jin-Won Jang

Eun-Chul Shin

Ki-Hong Song

Byeong-Hwan Kim

A method of driving a light-source module includes adjusting a frequency of a boosting switching signal based on a dimming signal which controls luminance of a light-emitting diode ('LED') string of the light-source module, where the LED string comprises a plurality of LEDs connected to each other in series, and controlling a main transistor in response to the boosting switching signal to transfer a driving voltage to the LED string.

Method of driving light-source with improved contrast ratio and display apparatus for performing the method

A backlight unit includes a light source part including a light-emitting diode array, a DC/DC converter, a driving current controller, and a reference voltage variable part. The backlight unit is operated in a first mode or a second mode. The driving current controller controls a driving current flowing through the light-emitting diode array to have a first current level during the first mode and controls the driving current flowing through the light-emitting diode array to have a second current level during the second mode. The reference voltage variable part applies a first reference voltage to the driving current controller during the first mode and applies a second reference voltage to the driving current controller during the second mode.

Backlight unit, display apparatus having the same, and image display system

Method of driving light-source and display apparatus for performing the method

A backlight unit includes a power converter configured to generate a light source driving voltage in response to a voltage control signal, a plurality of light emitting diode strings, where each of the light emitting diode strings receives the light source driving voltage through a first terminal thereof, a plurality of transistors corresponding to the light emitting diode strings, where each of the transistors includes: a first electrode connected to a second terminal of a corresponding light emitting diode string thereof; a second electrode; and a control electrode, and a controller connected to the control electrode and the second electrode, where the controller outputs a plurality of current control signals to control electrodes of the transistors and generate the voltage control signal, where the controller generates an over-current detection signal when any one of the current control signals has a pulse width less than a predetermined reference width.

Backlight unit with over-current detection and display device having the same

In a display device, a backlight unit including a power converter configured to generate a light source driving voltage in response to a voltage control signal, a plurality of light emitting diode strings each configured to receive the light source driving voltage through an end thereof, and a controller connected to the other end of each of the plurality of light emitting diode strings and configured to generate a plurality of current control signals used to control a current flowing through each of the plurality of light emitting diode strings and the voltage control signal. The controller is configured to generate the voltage control signal in response to a current control signal from among the plurality of current control signals, which is applied to a light emitting diode string configured to receive a lowest forward driving voltage among the plurality of light emitting diode strings.

Backlight unit and display device having the same

A backlight unit includes a power supply converter including a primary winding connected to an input power supply voltage, and a secondary winding which is connected to an output node and outputs a light emitting diode drive voltage to the output node in response to a mode signal and a switching control signal; and a light emitting diode string connected to the output node of the power supply converter, where the power supply converter serially connects a boosting winding to the secondary winding and the output node and when the mode signal represents a three dimensional image display mode, and outputs a boosted light emitting diode drive voltage to the output node through the boosting winding.

Backlight unit and display device including the same

A backlight unit includes a DC-DC converter; a voltage control unit which controls output voltage of the DC-DC converter; a plurality of unit light emitting diode arrays; and current deviation compensating unit in connection with input terminals of the plurality of unit light emitting diode arrays. The current deviation compensating unit receives the controlled voltage of the voltage control unit and transfers a feedback signal to the voltage control unit based on the received voltage, and actively compensates a current deviation generated by electrical characteristics of the plurality of unit light emitting diode arrays and transfers the compensated current deviation to the input terminals of the plurality of unit light emitting diode arrays.

Back light unit and display device including the same

A light source apparatus includes a plurality of light source parts, a power supply part, a current selection part and a current control part. The plurality of the light source parts are connected in parallel and the power supply part provides power to a first terminal of each of the light source parts. The current selection part selects the current level of one of the light source parts as a reference current level. The current control part adjusts the levels of the currents flowing through the light source parts to be substantially equal to the reference current level. Selection of the light source part that provides the reference current level is dynamically changed.

Method of driving a light source, light source apparatus for performing the method and display apparatus having the light source apparatus

A method of driving a light source includes outputting a variable driving voltage to a light source part, sensing a first voltage based on the driving voltage and developed at a first end of the light source part, sensing a second voltage developed at a second end of the light source part due to current passing through the light source part and adjusting the driving voltage while using the first and second voltages so that power consumption by the light source part is substantially constant irrespective of temperature of the light source part and/or irrespective of a duty cycle ration being used to drive the light source part. Thus, a luminance of the light source part may be maintained at substantially uniform levels.

A method for driving a light source and maintaining its target white color coordinates despite of varied and decreased light source luminance includes detecting an amount of colored light generated from a plurality of colored light sources, comparing detected colored light to reference data and verifying that colored light source has the correct preset duty cycle. If the colored light source is driven by the preset duty cycle, the method includes modifying the reference data based on the detected light from the colored light source and adjusting the amount of colored light by controlling a driving signal to the colored light sources based on the modified reference data.

Method for driving a light source apparatus with varying luminance and a display apparatus having the light source apparatus

A connector for a light source module includes a body portion and a terminal portion. The body portion includes a first opening portion and a second opening portion. The first opening portion receives a portion of the light source module. The second opening portion receives a portion of a light source driver which drives the light source module. The terminal portion includes a first terminal and a second terminal. The first terminal is in the first opening portion of the body portion. The second terminal is connected to the first terminal. The second terminal is in the second opening portion of the body portion.

Connector for light source module and backlight assembly having the same

A display apparatus includes a backlight unit which emits a light, and a display panel which receives the light to display an image. The backlight unit includes a driving circuit which outputs a driving voltage and a reference voltage; and p light source blocks connected to the driving circuit, p being a natural number greater than or equal to 2, where each light source block of the p light source blocks receives the driving voltage through a first terminal thereof and the reference voltage through a second terminal thereof to generate the light, and the p light source blocks are divided into a plurality of groups, each group including at least two light source blocks. The driving circuit includes a first switching section which applies the driving voltage to first terminals of the p light source blocks, and a second switching section which applies the reference voltage to the second terminal of at least one of the p light source blocks.

Display apparatus

A backlight unit includes a driving circuit, a plurality of light source strings, and an error detector. The driving circuit outputs a driving voltage. Each of the light source strings includes a plurality of light sources and receives the driving voltage through input terminals of the light source strings to generate a light. The error detector is connected to output terminals of the light source strings and senses voltages between the input terminals and the output terminals of the light source strings to detect an error in the light sources using a first voltage and a second voltage. The first voltage is a voltage difference between a maximum and a minimum of the sensed voltages and the second voltage is obtained by dividing one sensed voltage of the sensed voltages by a number of the light sources of a light source string from which the one sensed voltage is sensed.

Backlight unit, driving method thereof, and error detection method thereof

A liquid crystal display ('LCD') includes; a lower receiving container which includes; a bottom plate, sidewalls extending from the bottom plate, a first through-hole formed in the bottom plate, and a guide pole disposed on the bottom plate and which substantially surrounds the first through-hole, a plurality of light sources disposed within the lower receiving container; an optical sensor printed circuit board ('PCB') attached to a bottom surface of the bottom plate, wherein the optical sensor printed circuit board covers the first through-hole, and an optical sensor mounted on the optical sensor PCB and inserted into the first through-hole.

Liquid crystal display

A backlight unit includes light source groups, a converter, a compensator, a detector and a protector. Each of the light source groups includes a light source, and the converter boosts an input voltage to a driving voltage that is supplied to the light source groups. The compensator is connected to the light source groups and compensates a deviation between currents fed back to the compensator from each of the light source groups. The detector is connected between the compensator and the light source groups and detects a maximum voltage from among feedback voltages fed back to the compensator from each of the light source groups. The protector is connected to the detector and receives the maximum voltage, and compares the maximum voltage to a reference voltage to generate a compared result. The protector outputs a protection signal to the converter based on the compared result.

Growing community of inventors

Asan-si, South Korea

Min-Soo Choi