Light Emitting Materials

LED - Light Emitting Diode



1920, from an accidentally discovered of Oleg Vladimirovich Losev, a radio technician, the symtom of a diode in radio receiver emitting light when the current pass through became nowadays Light Emitting Diodes or LED.


Image courtesy of Wikipedia

The inner working of LED



Current flow from the p-side/anode(+) to the n-side/cathode(-) in one way only. Electrons from cathode(-) and hole from anode(+) meeting each other at the junction point, falling into a lower state of energy and release energy in the form of a photon.

Typical structure of a LED



Light colors & material

	Color	Wavelength [nm]	Voltage [V]	Semiconductor Material
	Infrared	λ > 760	ΔV <>	Gallium arsenide (GaAs) Aluminium gallium arsenide (AlGaAs)
	Red	610 < λ <>	1.63 < ΔV <>	Aluminium gallium arsenide (AlGaAs) Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP)
	Orange	590 < λ <>	2.03 < ΔV <>	Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP)
	Yellow	570 < λ <>	2.10 < ΔV <>	Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP)
	Green	500 < λ <>	1.9 < ΔV <>	Indium gallium nitride (InGaN) / Gallium(III) nitride (GaN) Gallium(III) phosphide (GaP) Aluminium gallium indium phosphide (AlGaInP) Aluminium gallium phosphide (AlGaP)
	Blue	450 < λ <>	2.48 < ΔV <>	Zinc selenide (ZnSe) Indium gallium nitride (InGaN) Silicon carbide (SiC) as substrate Silicon (Si) as substrate — (under development)
	Violet	400 < λ <>	2.76 < ΔV <>	Indium gallium nitride (InGaN)
	Purple	multiple types	2.48 < ΔV <>	Dual blue/red LEDs, blue with red phosphor, or white with purple plastic
	Ultraviolet	λ <>	3.1 < ΔV <>	diamond (C) Aluminium nitride (AlN) Aluminium gallium nitride (AlGaN) Aluminium gallium indium nitride (AlGaInN) — (down to 210 nm)
	White	Broad spectrum	ΔV = 3.5	Blue/UV diode with yellow phosphor

Common Types

Organic light-emitting diodes (OLEDs)

LED with an organic compound as the emitting layer. The emitting compound can be a small organic molecule in a crystalline phase or a polymer.

OLEDs are lighter than LED, have a wider range of color and more flexible. It can be applied to low-cost flexible displays, light sources, thin decoration layers or even luminous cloth.

Advantages:

- Efficiency
- Emit light with a designated color
- Compact size
- Fast respond to on/off switch
- Longevity
- Physical force resistance
- No toxic

Disadvantages:

- Color range: the incomplete of the white spectrum of LED can cause some misread in objects color
- Blue pollution: cool-white Leds can emit much more blue light than conventional light sources that may cause light pollute in some area of the urban area.

Wood Materials

A:  Wood Materials


   I.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 

   II.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 


   III.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 


   IV.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 



 

Ceramic Materials

A:  Ceramic Materials


   I.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 

   II.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 


   III.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 


   IV.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 



 

Metal Materials

A:  Metal Materials


   I.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 

   II.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 


   III.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 


   IV.  Stuff
       Note information here about the type of class
                    Insert an image of the glass specified.
                        Site the example.

   

               1. How is this glass used?
               2. How is this glass composed?

               3. How did the make up of the component change from other glasses? 



 

Concrete Materials

A:  Concrete Materials


   I.  Traditional Concrete

       

Traditional Concrete Samples

Image source by www.wfdecor.com

 


                      

How is it made?

Concrete requires the right temperature and the basic three components; Portland cement, water, and aggregate (rock and sand). When mixed together appropriately, additional additives made me include such as:

Accelerating admixture

   Calcium, reduced seeting time and accelerates strength.

Retarding admixture

   Retarder is set in hot weather condition to delay setting time.

Fly Ash

   A by-product of coal burning plants. Fly ash can replace up to 15-30% of cement mix. It helps improve workability, increses air entrainment by durability, and provides a mroe workable mixture.

Molecular structure of concrete 

 

Molecular structure of concrete
Image source by www.elkem.no








   II.  Shotcrete

Shotcrete concrete being sprayed
Image source by www0.planete-tp.equipement.gouv.fr

   

How is it made?

A form of concrete that uses the basic applied properties of traditional concrete except it's final process is different. Shotcrete is concrete, funneled through a tube to pour onto a slab or wall on site into a formwork or frame. The are two primary methods of applying shotcrete; dry-mix and wet-mix.


Dry-mix
This occurs when the aggregates and cement are mixed together. the materials is sent through the tube system to be compressed by air and meeting water at the nozzle to mix it.


Wet-mix
The elements of concrete are pre-mix and the material is sent through a tube system. The concrete is funneled through the tube until it meets the compressed air, used for spray

MACRO Links

LINKS

A.1.1:  GLASS

1. Sony Glass Lab
2. Precision Glass Bending
3. MACOR - Machinable Glass Ceramic
4. LennTech
5. Glass Department of Materials
6. Fusion Glass Designs

A.1.2:  Crafts and Products

1. SSGI Decorative
2. LiveTile
3. RubinoGlass
4. Bevel
5. Contract Glass
6. Star Shine
7. B. Sweden
8. Orrefors

A.1.3  Industrial

1. Merkad
2. ColorLites
3. Saint Gobain Glass
4. Asahi Glass Company
5. Corning
6. Schott

PolyCrystalline Solids

A.1.4: What is an PolyCrystalline Solid?

Input information here

Crystalline Solid

A.1.3: What is an Crystalline Solid?

Input information here

Amorphous Solid

A.1.2: What is an Amorphous Solid?

An amorphous solid is the composition of atoms and their arrangement of long-range atomic order known as crystalline solids or morphous. Materials that are classified under amorphous solids are glass and cotton candy. There are a full-range of glass materials that act as semiconductors, insulators, and metals. The solid composes a transitional setting between transformation of atoms and electrical conductivity that permit the energy and material to behave with the corresponding crystalline metal. This order further enhances the composition of glass as it is transformed from a liquid to a solid state.

Image: The atomic structure of an amorphous solid; representation

of its long-range order of atomic compounds.

Image by European Laboratory for Non-Linear Spectroscopy

Examples of amorphous solids
Image of glazing system (left). Image of cotton candy (right).
Image by Gingersus

Glass Materials

A:  Glass Materials


   I.  Textured Glass

        












Deep-wave water textured glass
Image from Fusion Glass Designs

1. How is this glass composed? 

There are two primary way for this glass to be produce, by kiln-cast and by standard float glass. The kiln-cast process occurs by forming the float glass over the moulds to create the textures. The glass is heated to melt into the mould and cooled to release the final product. The standard float glass  is laid over a ceramic sand, plaster or concrete moulds. The glass is heat, relaxing the glass material so that it can pick up the mould tecture, then it is slowly cooled and annealed.

	Type Textured Glass Main material Kiln cast and standard float glass Thickness At least 4-25mm Size Available up to 3150 - 1750mm Typical Uses Partitions, doors, screens, flooring, lighting, cladding, balustrades, counters, sculpture

   II.  Gorilla Glass

        

Gorilla Glass
Source from Corning.com.

1. What is this used for? 

It is an environmentally friendly product that uses alkali-aluminosilicate thin sheet glass. The texture is a composition of chemicals durability and strength on most applications. The sheet is both strong and damage resistant.

	Type Gorilla Glass Main material Alkali-aluminosilicate Thickness At least 0.5-2.0mm Size Available up to 1250x900mm thin s Chemical makeup HCI (5%), NH4F:HF (10%), HF (10%), NaOH Typical Uses Protective cover for electronic displays; cell phones, laptop, mobile devices, touchscreen, optical components, and high strength glass.

              




   III.  Fibre Optics

        

Fiber optics

Image from Wiki

1. How is this glass composed? 

Fiber optics is a strand of glass, thin and long, that enable light and electrical pulses to pass through, allowing information to pass through. The round corners of the component and its properties enhance the ability of light and waves to transmit by looping, bending, twisting, and winding through the glass.  It is composed of glass core with a silica sleeve where the core allows the transmission of data and the silica sleeve stops the information from going beyond the tube. 

How is it made?

The fiber optic is produce by a process call modified chemical vaopor deposition. Through this process, oxygen is bubble through silicon chloride liquid, germanium chloride, and other chemicals to bond the pyhsical and optical properties such as refraction, coefficient of expansion, and melting point.  Then gas vapors are conducted in a synthetic silica or quartz tube where the torch is turned up and moves along the outside tube. This source of heat causes two things:

• The silicon and gernamium chemicals react with oxygen, forming the silicon dioxid and germanium dioxide.
• Silicon and gernanium dioxide bond together, fusing itself into the glass tube. 

The glass purity is maintained by adding corrosion-resistant plastic in the system, controlling the flow and composition of the mixture. 

Fiber optics atomic structure with silica

Image from Wiki

 











Fiber optics process

Image from Hikari optic bozai

	Type Fiber Optics Main material pure optical glass, silicon dioxide, germanium dioxide, silica sleeve Thickness At least 2-12mm Size Available up to any length Typical Uses Communications, lighting, wireless, networking, electrical devices, etc.

   IV. Self-cleaning Glass

        

Self Cleaning Glass
Source from Pilkington Activ.

1. What is this used for? 

A simple glass sheet with an ultraviolet light absorber to break down and loosen deposits that make it easy for the rain to wash away. The product, developed by Teflon needs no secondary process other than a simple application of the cerium oxide film on the exterior. The material must absorb enough UV rays in order for the system to work.

	Type Self-cleaning Glass Main material Silicate, cerium oxide film Thickness At least 0.5-2.0mm Size Available up to any size Chemical makeup SiO2,  CeO2 Typical Uses Commercial glass, office buildings, houses, automotive.

   V.  Tempered Bent Glass

                    










Tempered Bent Glass

Source from Precision Glass Bending Co.





    

Image from momoy.com

1. How is this glass used?

Various uses range from architectural elements like a curtain wall, green house, to glass domes. 

2. How is this glass composed?

3. How did the make up of the component change from other glasses? 

   VI.  Film Glass type

       Resistive touch panels

                  

 Image from Sony Labs

    

Image from Sony Labs

1. How is this glass used?

This type of glass is typically used for electronic devices such as; audio and visual, cell phones, and game machines. 

2. How is this glass composed?

                      

Most of the glass product is from a PE Glass film. There are two outer layers, the Upper and lower electrode glass film. Through additional elements, the glass becomes a touch sensitive responder because of the FPC (Flexible print circuit) and the double coated tape sandwiched between the electrodes.  
             

		Type FG Type Main material PE base film-glass Thickness At least 0.96 mm Rate for transparency At least 82 % Input method Polyethylene pen or finger FPC Polyimide base, Cu wiring Size 2 to 5 inches

           



 

Wood

Wood is a fascinating material in terms of both its structure and mechanical performance. It is an ecologically friendly construction material since it is a renewable resource and, indeed, the energy required to produce unit weight of timber is lower than for any other building material. Wood is also cheap – it costs sixty times less than steel per tonne. Wood is a low-density, cellular polymeric composite and consequently does not fall into any one category of material.

Internal Structure:









Fig. 1 Diagrammatic illustration, showing the principal structural features, of a wedgeshaped
segment cut from a mature hardwood tree [after J.M. Dinwoodie, J.Microscopy,
104(1), 1975].

Wood, predominantly, has a structure comprising parallel, columnar cells (see figure 2). The elongated cells can be considered as fibres, embedded in a matrix of the polymer lignin. The cell walls contain helical windings of cellulose microfibrils.

















Fig. 2 Simplified structure of the cell wall showing orientation of the microfibrils in each of
the major wall layers [after J.M. Dinwoodie, J.Microscopy, 104(1), 1975].

The exact microstructure of wood depends on whether the material is derived from coniferous trees (softwood) or broad-leaved trees (hardwood). In both types of wood, 90-95% of the cells are aligned along the vertical axis, while the remainder are in the radial directions. There are no cells in a tangential (or hoop) orientation. The distribution of cells is different in all three principal sections (in cross section, tangential section and radial section as illustrated in Figure 1) and wood is therefore very anisotropic. There are four different types of cells in hardwood.

• Parenchyma cells (200 - 300 μm in diameter these cells are responsible forcarbohydrate storage and can be aligned horizontally or vertically);
• Tracheids (which perform the function of both storage and support);
• Vessels (responsible for conduction, these are cells whose end walls have beendissolved away and they are short - 0.2-1.2 mm, and wide - approx. 0.5 mm);
• Fibres (these provide the principal source of support and they are long (1 -2 mm)with an aspect ratio of 100:1).

However, when observing the microstructure of a hardwood sample in practice it is normally only easy to see the vessels, fibres and parenchyma cells, since the tracheids are very few in number.

(source: University of Cambridge, Department of Materials Science, Microstructures and Mechanical properties of Wood, December 2008)














Wood-Cedar-Eastern-Juniperus Virginiana-cross-section














Wood-Cedar-Eastern-Juniperus Virginiana-longtitude-section














Wood-Cedar-Eastern-Juniperus Virginiana-radical-section

Image courtesy of MicrolabNW Photomicrograph Gallery


Bonding Force











The bounding force inside a wooden volume base on the cellulose cells' wall.

















Sectional view of a soft wood plank (Conifers which may have scale-like (cedar wood) or needle-like leaves (pines)). Image courtesy of Paulo Monteiro, University of California Berkeley, Introduction to Wood lecture.


















Sectional view of a hard wood plank (Broad leaf trees (oak)). Image courtesy of Paulo Monteiro, University of California Berkeley, Introduction to Wood lecture.

As of the two above image, we can see wood is best for bearing pressure along its fiber direction because the pressure is distribute equally along its cells' wall. Tension can be distribute pretty good along the cell's axis too, but a significant length before the brace's end must be consider to avoid splitting. Build up from straws packed fiber cells, wood provide a certain level of bending but not so much because the fiber cell would shrink. For longitudinal, tangential and radial directions, wood's ability to stand cutting force is worst.

Shrinkage:













Image courtesy of Paulo Monteiro, University of California Berkeley, Introduction to Wood lecture.

Sawing Lumber:

















Image courtesy of Paulo Monteiro, University of California Berkeley, Introduction to Wood lecture.


Non-Conventional Usage



Alvar Aalto's Paimio Chair.

By sticking many layer of plywood under a constraint bending force, Aalto had successfully force wood to bend into curvature but also keep its elastic and aesthetic.



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Metals

Largely use in construction, metal long been a significant element of architecture. Working from inside the concrete structure to outside skin, metal plays a major part due to its characteristic: longevity, durable, persistent & weather proof. To understand how could a simple material archive so many strong characteristic, we have to look into its internal structure & molecular.


Internal Structure

Although surprisingly airy, the microcrystalline of metal still provide the most hardness because it formed from simple, three-dimensional pattern which spread the impact force approximately in all direction of the structure.














Image courtesy of Emergent


















Distribution of Aluminum grains


Atomic and Molecular Structure



















Gold diatom












Magnet diatom

Bonding Force


















Alternative Usage

base on the change in atoms structure





















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