Showing posts with label Samsung. Show all posts
Showing posts with label Samsung. Show all posts

Monday, February 21, 2011

Researchers fabricate first large-area, full-color quantum dot display

February 21, 2011 by Lisa Zyga

quantum dot display

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Electroluminescence image of a four-inch full-color quantum dot display with a resolution of 320 x 240 pixels. Image credit: Tae-Ho Kim, et al. ©2011 Macmillan Publishers Limited.

(PhysOrg.com) -- For more than a decade, researchers have been trying to make TV displays out of quantum dots. Theoretically, quantum dot displays could provide extremely high-resolution images and higher energy efficiencies than current TVs. Now in a new study, researchers have presented the first large-area, full-color quantum dot display that could lead to the development of displays for the next-generation TVs, mobile phones, digital cameras, and portable game systems.

The researchers, Tae-Ho Kim and coauthors from various institutes in South Korea, have published their study on the first four-inch, full-color quantum dot display in a recent issue of Nature Photonics. The display consists of a film printed with trillions of the tiny (an average of 3 trillion per cm2). The quantum dots emit light at a specific wavelength (color) that can be tuned by changing the size of the quantum dots.

Previous attempts to make full-color quantum dot displays have faced challenges in that image quality tended to decrease with the size of the display. To overcome this challenge, the researchers in the current study used a different method for applying the quantum dots to the film’s surface. Instead of spraying the quantum dots onto the film, the researchers created an “ink stamp” out of a patterned silicon wafer. They used the stamp to pick up strips of size-selected quantum dots, and then stamp them onto the substrate. Unlike the spraying methods, this method does not require the use of a solvent, which previously reduced color brightness.

As the results showed, the new quantum dot display has a greater density and uniformity of quantum dots, as well as a brighter picture and higher energy efficiency than previous quantum dot displays. The new display is also flexible, so applications could include roll-up portable displays or flexible lighting applications. The technology could also be used in photovoltaic devices, which would especially benefit from quantum dots’ high energy efficiency.

More information: Tae-Ho Kim, et al. “Full-colour quantum dot displays fabricated by transfer printing.” Nature Photonics. DOI:10.1038/nphoton.2011.12.
via: Nature News

Source

Tuesday, November 11, 2008

Report: Samsung SDI Investigating the Use of CNT in BLUs (July 16)

Industry officials revealed that Samsung SDI is in the process of considering carbon nanotube (CNT) material for use in its backlight unit (BLU) business, Display Bank reported on July 8.

Display Bank cited industry sources as stating that Samsung SDI has completed development of next-generation CNT BLU, which would emerge as the next technology in backlighting applications, after CCFL and LED. The company is exploring using the technology in various electronic products including LCD TVs larger than 40 inches.

According to Display Bank, CNT BLU could measure less than 1cm thick, and would offer benefits of both CCFL and LED BLU. A Samsung SDI-related spokesperson confirmed the "ongoing research of CNT BLU" to Display Bank but would not offer any specifics.

Source

Tuesday, May 27, 2008

Method of fabricating memory device utilizing carbon nanotubes

United States Patent 7,378,328 Choi, et al., May 27, 2008

Abstract

A fast, reliable, highly integrated memory device formed of a carbon nanotube memory device and a method for forming the same, in which the carbon nanotube memory device includes a substrate, a source electrode, a drain electrode, a carbon nanotube having high electrical and thermal conductivity, a memory cell having excellent charge storage capability, and a gate electrode. The source electrode and drain electrode are arranged with a predetermined interval between them on the substrate and are subjected to a voltage. The carbon nanotube connects the source electrode to the drain electrode and serves as a channel for charge movement. The memory cell is located over the carbon nanotube and stores charges from the carbon nanotube. The gate electrode is formed in contact with the upper surface of the memory cell and controls the amount of charge flowing from the carbon nanotube into the memory cell.

Inventors: Choi; Won-bong (Yongin, KR), Yoo; In-kyeong (Suwon, KR), Chu; Jae-uk (Gwangmyeong, KR)

Assignee: Samsung Electronics Co., Ltd. (Suwon, Kyungki-do, KR)

http://tinyurl.com/56r5a3

I'm all for it - the more the merrier - Keesmann agrees, I hope.

Phase changeable memory devices including carbon nano tubes

United States Patent 7,378,701 Hideki May 27, 2008, Samsung

Abstract

An integrated circuit phase changeable memory device includes an integrated circuit substrate, a first electrode on the integrated circuit substrate, and a second electrode on the integrated circuit substrate and spaced apart from the first electrode. A carbon nano tube and a phase changeable layer are serially disposed between the first and second electrodes. An insulating layer can include a contact hole and the carbon nano tube may be provided in the contact hole. Moreover, the phase changeable layer also may be provided at least partially in the contact hole. A layer also may be provided at least partially surrounding the carbon nano tube in the contact hole. Related fabrication methods also are provided.

Inventors: Hideki; Horii (Seoul, KR)

Assignee: Samsung Electronics Co., Ltd. (KR)

http://tinyurl.com/4t5yd4

Not sure if this is coincidental, but here it is - same issue day as UMK's offering and very similar. I think the USPTO lets them slug it out together outside the patent office as to who owns what. UMK's was magnetic while this one is phase change so that could be the distinction.

Monday, May 19, 2008

Field emission boosts Samsung LCD contrast to 300,000

Samsung has demonstrated an LCD with a field emission backlight (FEB) - achieving a claimed 300,000:1 contrast ratio.

Key to this astonishingly high contrast - using a LCD panel, where 1,500:1 is generally the limit - is to make a backlight of a course array of pixels, and to turn off the pixels behind dark areas of the screen.

In Samsung's case, the backlight is broken into 2,800 (70x40) 1cm squares behind the 32in. LCD, and each of these pixels can be brightened as well as extinguished.

Between LCD and backlight, a translucent sheet blurs the squares preventing their sharp edges being seen through the LCD.

Field emission devices use sharp points in a vacuum as electron sources, and a high voltage to accelerate these electrons in to a phosphor screen.

In this case, the FEB uses carbon nanotubes as emissive tips and a triode structure including a grid to allow each 1cm square to be modulated.

The cathode is a tangle of nanotubes deposited on a flat surface, treated with an elastomer which encourages the free ends of exposed nanotubes stand up straight. This creates a random forest of emissive tips.

Above this sits the control grid for each square which has 120x120 40[micro]m holes on a 70[micro]m pitch for electrons to pass through.

Above this is the transparent anode, biased to 15kV, coated with a mixed red-green-blue phosphor.

The backlight produces 6,000cd/m2, reduced by 95 per cent by the inherent absorption of the LCD panel.

Current density in the emissive tips, said Samsung, is low enough to expect long life from the backlight.

Source

Saturday, May 17, 2008

Samsung - United States Patent 7,372,194 - Moon, May 13, 2008

Electron emission source composition for flat panel display and method of producing electron emission source for flat panel display using the same

Abstract

Disclosed is an electron emission source composition for a flat panel display using the same, comprising carbon nanotubes, a vehicle, and an organotitanium or an organometallic compound, and a method of producing the electron emission source composition having improved adherent strength with the substrate and providing stable and uniform electron emitting characteristics.

Inventors: Moon; Jong-Woon (Busan, KR)
Assignee: Samsung SDI Co., Ltd. (Suwon, KR)

What is claimed is:

1. A flat panel comprising: a substrate; an electrode formed on the substrate; and an electron emission source layer formed on the electrode, a surface of the layer having micro-cracks in a range of about 0.1 .mu.m to about 100 .mu.m, wherein the electron emission source layer comprises: carbon nanotubes; a vehicle; and an organotitanium crack formation compound or an organometallic crack formation compound.

2. The flat panel of claim 1, wherein the carbon nanotubes are present in a range of 5 wt % and 80 wt %, and the organotitanium crack formation compound or the organometallic crack formation compound is present in a range of 20 wt % and 95 wt %.

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7,372,194.PN.&OS=PN/7,372,194&RS=PN/7,372,194

Kinda reminds me at first glance (!!) of a combination of SED and CNT, cracks and C nanotubes in those micro-cracks - between 0.1 and 100 mu.m across (X by 1000 to get nm).

Moon me!

Samsung rules!!

Tuesday, May 6, 2008

The high contrast ratio and fast response time of a liquid crystal display lit by a carbon nanotube field emission backlight unit

Young Chul Choi et al 2008 Nanotechnology 19 235306 (5pp) doi: 10.1088/0957-4484/19/23/235306 Help

PDF (943 KB) | References


Young Chul Choi, Ji Won Lee, Su Kyung Lee, Mun Seok Kang, Chang Soo Lee, Kyu Won Jung, Ji Hong Lim, Jong Woon Moon, Myung Ick Hwang, Il Hwan Kim, Yun Hee Kim, Byong Gon Lee, Hyung Rae Seon, Sang Jin Lee, Jong Hwan Park, Yong C Kim and Hun Soo Kim
Display Laboratory 3 Group, Corporate R&D Center, Samsung SDI, 428-5, Gongse-dong, Giheung-gu, Yongin, Gyeonggi 446-577, Republic of Korea
E-mail: hs88.kim@samsung.com

Abstract. We report on the fabrication of a carbon nanotube field emission backlight unit (CNT-BLU) and its application for liquid crystal displays (LCD). The CNT-BLU was operated with locally controllable luminance and impulse-type scanning. The local luminance control, which is based on a very small block size of 1 cm2, consisted of local dimming and local brightening. This resulted in the contrast ratio of the LCD-TV to be as high as 300 000:1. A fast response time of ~5.7 ms was also achieved from the LCD-TV lit by CNT-BLU, originating from the impulse-type scanning. In addition, the CNT-BLU showed long-term emission stability and high luminance uniformity.

Print publication: Issue 23 (11 June 2008)
Received 7 March 2008, in final form 10 April 2008
Published 6 May 2008

Source

Conclusion - from PDF:

4. Conclusion
We have developed an FE-BLU using a CNT emitter (CNTBLU), and then analyzed its field emission characteristics including emission current, stability and uniformity. Well distributed CNTs were precisely integrated into gate holes through simple photolithography and a surface treatment process. The CNT-BLU generated high emission current with long-term stability and the observed emission uniformity was high enough to be used for an LCD-TV. The image characteristics of an LCD-TV lit by the CNT-BLU were evaluated and compared with those by a CCFL. Compared with a CCFL backlight, at least 200 times enhanced contrast ratios and three times improved response times were demonstrated by using the CNT-BLU. These were achieved by fine local luminance control and impulse-type scanning, respectively. Achieving these technologies using CNT emitters is believed to be very promising for the next-generation LCDs with excellent image characteristics.

Tuesday, April 29, 2008

Samsung USP 7,365,482, April 29, 2008 - CNT FED




United States Patent 7,365,482
Ryu , et al. April 29, 2008

Field emission display including electron emission source formed in multi-layer structure

Abstract

A field emission display includes first and second substrates provided opposing one another with a predetermined gap therebetween; electron emission sources provided on one of the first and second substrates; an electron emission inducing assembly for inducing the emission of electrons from the electron emission sources; and an illuminating assembly provided on the substrate on which the electron emission sources are not formed, the illuminating assembly realizing images by the emission of electrons from the electron emission sources. The electron emission sources include a carbon nanotube layer and a base layer, the base layer connecting the carbon nanotube layer to the substrate and applying a voltage to the carbon nanotube layer required for the emission of electrons. Also, the carbon nanotube layer is provided on the base layer in a state substantially un-mixed with the base layer.


Inventors: Ryu; Mee-Ae (Suwon, KR), Kim; Hun-Young (Seoul, KR), Nam; Joong-Woo (Suwon, KR)
Assignee: Samsung SDI Co., Ltd. (Suwon-si, Gyeonggi-do, KR)
Appl. No.: 10/684,520
Filed: October 15, 2003

What is claimed is:

1. A field emission display, comprising: first and second substrates provided opposing one another with a predetermined gap therebetween to form a vacuum assembly; electron emission sources provided on one of the first and second substrates; an electron emission inducing assembly inducing the emission of electrons from the electron emission sources; and an illuminating assembly provided on the other one of the first and second substrates not including the electron emission sources being formed, the illuminating assembly realizing images by the emission of electrons from the electron emission sources, with the electron emission sources including a carbon nanotube layer and a base layer, said base layer having an outer surface that includes prominences and depressions, the base layer formed between the carbon nanotube layer and the one of the first and second substrates on which the electron emission sources are provided and having conductibility for applying a voltage to the carbon nanotube layer required for the emission of electrons, the carbon nanotube layer comprising a plurality of carbon nanotubes, and with the base layer having a predetermined thickness, and the carbon nanotube layer being provided on the base layer in a state substantially un-mixed with the base layer, the carbon nanotubes formed on both of the prominences and the depressions, wherein the base layer comprises: an adhesive material realized through a glass frit that selected from the group consisting of PbO, SiO.sub.2, Ba.sub.2O.sub.3, and a mixture thereof; and a metal conductive material selected from the group consisting of silver, copper, and aluminum.

Source

Tuesday, March 25, 2008

United States Patent 7,348,274 - Samsung


Method of aligning carbon nanotubes and method of manufacturing field emission device using the same

Abstract

A method of aligning carbon nanotubes (CNTs) and a method of manufacturing a field emission device (FED) using the same, wherein a mold having an intaglio pattern is prepared, an aqueous solution containing an amphiphilic organic material and the CNTs are coated on a surface of a substrate, the mold is adhered to the substrate surface to cause the aqueous solution to flow into the intaglio pattern by a capillary force, and the mold is removed from the substrate surface to vertically align the CNTs on the substrate surface.


Inventors: Chung; Deuk-Seok (Seongnam-si, KR), Oh; Tae-Sik (Suwon-si, KR), Bae; Min-Jong (Anyang-si, KR)
Assignee: Samsung SDI Co., Ltd. (Suwon-si, Gyeonggi-do, KR)
Appl. No.: 11/225,174
Filed: September 14, 2005

Link




Saturday, February 2, 2008

Backlight +CNT Patents

LINK

1-3 are assigned to SAMSUNG