Light bulb

LeeF….Living in the Light..Driving with the Wind..

We are a young entity with strategy based on our core competence, Engineering and the change we foresee in households and industries, Innovation. Within a short time we have invested in major interests of the general public, conserving energy to particular needs of interest groups, ground braking designs. Our visions lie with sustainable energy and consumer electronics. Creative Thinking, Practical Innovations, Quality Standards and Customer Empowerment approach govern our objectives. Crafting our technology into the grasp of every house hold and embedding innovation as agents of efficiency, quality and class is our special skill. We believe in team work, commitment, and constant improvement to realize the wildest dreams of our customers.

Saturday, November 3, 2012

Rivira Article about LeeF


Wednesday, October 17, 2012

Now LeeF Reaching closer to you



 
LeeF LED lamps are conquering the lighting industry, providing best solution to your lighting requirements. Now LeeF is out there in WWW, conquering the web, reaching you easier than ever before.
 
leef.lk was released to cyber space, today, 15th October 2012 at the official web launch in a gathering of the company shareholders held within the premises of University of Moratuwa. The website was launched at 11.00 a.m. by the president of LeeF, Rishan Akalanka after the IT director Chamika Kasun officially addressed the gathering on the .lk domain.
 
The website includes the basic information of the organisation, the product details and pictures, the services offered and contact information. The web site is equipped with newest technology to enhance capabilities and user friendliness.   It is the result of the hard work of LeeF IT initiative spearheaded by IT director Chamika Kasun and his crew.
  
All the LeeF product details and services are now available just for you all at one place at your finger tips. Visit us today and experience the LeeF technology.
 
Visit us at www.leef.lk and Feel the belief.

Wednesday, October 10, 2012

LIGHT emitting DIODES - LIFE enlightening DIODES



LIGHT emitting DIODES  -   LIFE enlightening DIODES

It is with a bit of an exaggeration I started conglomerating my ideas. LED s just another invention? I don’t think so…There are thousands of points to contradict the idea, millions of examples to eradicate this idea, but thirty engineers to eliminate this misconception and root the contemporary innovation of LED bulbs to enhance the development of the LED s……..

light-emitting diode (LED) is a semiconductor light source.  LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Appearing as practical electronic components in 1962, early LEDs emitted low-intensity red light, but modern versions are available across the visibleultraviolet, and infrared wavelengths, with very high brightness.
So the year 1962 brought a different kind of experience to those who wanted to minimize the concept of lighting, and this special day was the 9th of October. So the 9th of October brings foliage of refreshing memories to those who are engaged in the industry of LED lamps.
LeeF being one of those exclusive companies, would like to relish the memories of everybody who are interested in LEDs.  The history states……
“The first known report of a light-emitting solid-state diode was made in 1907 by the British experimenter H. J. Round. However, no practical use was made of the discovery for several decades. Independently, Oleg Vladimirovich Losev published "Luminous carborundum [[silicon carbide]] detector and detection with crystals" in the Russian journal Telegrafiya i Telefoniya bez Provodov (Wireless Telegraphy and Telephony).  Losev's work languished for decades.

The first practical LED was invented by Nick Holonyak, Jr., in 1962 while he was at General Electric Company. The first LEDs became commercially available in late 1960s, and were red. They were commonly used as replacements for incandescent indicators, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment………….
Nick Holonyak
But today the world revolves in a complete different way in which most of the tiny, One thing for sure, when we list down the applications of LED, you will be mesmerized, but it is true……
  •          Architectural lighting 
  •          Status indicators on all sorts of equipment
  •          Traffic lights and signals 
  •          Light source for machine vision systems, requiring bright, focused, homogeneous and possibly strobed illumination. 
  •          Exit signs 
  •          Motorcycle and Bicycle lights 
  •          Toys and recreational sporting goods, such as the Flashflight 
  •          Railroad crossing signals 
  •          Continuity indicators 
  •          Flashlights, including some mechanically powered models. 
  •          Light bars on emergency vehicles. 
  •          Elevator Push Button Lighting
  •          Thin, lightweight message displays at airports and railway stations and as destination displays for trains, buses, trams and ferries. 
  •          Red or yellow LEDs are used in indicator and alphanumeric displays in environments where night vision must be retained: aircraft cockpits, submarine and ship bridges, astronomy observatories, and in the field, e.g. night time animal watching and military field use. 
  •          Red, yellow, green, and blue LEDs can be used for model railroading applications 
  •          Remote controls, such as for TVs and VCRs, often use infrared LEDs. 
  •          In optical fiber and Free Space Optics communications. 
  •          In dot matrix arrangements for displaying messages. 
  •          Glowlights, as a more expensive but longer lasting and reusable alternative to Glowsticks. 
  •          Grow lights composed of LEDs are more efficient, both because LEDs produce more lumens per watt than other alternatives, and also because they can be tuned to the specific wavelengths plants can make the most use of. 
  •          Movement sensors, for example in optical computer mice 
  •          Because of their long life and fast switching times, LEDs have been used for automotive high-mounted brake lights and truck and bus brake lights and turn signals for some time, but many high-end vehicles are now starting to use LEDs for their entire rear light clusters. Besides the gain in reliability, this has styling advantages because LEDs are capable of forming much thinner lights than incandescent lamps with parabolic reflectors. The significant improvement in the time taken to light up (perhaps 0.5s faster than an incandescent bulb) improves safety by giving drivers more time to react. It has been reported that at normal highway speeds this equals 1 car length increased reaction time for the car behind. 
  •          Backlighting for LCD televisions and displays. The availability of LEDs in specific colors (RGB) enables a full-spectrum light source which expands the color gamut by as much as 45%. 
  •          New stage lighting equipment is being developed with LED sources in primary red-green-blue arrangements. 
  •          Lumalive, a photonic textile 
  •          LED-based Christmas lights have been available since 2002, but are only now beginning to gain in popularity and acceptance due to their higher initial purchase cost when compared to similar incandescent-based Christmas lights. For example, as of 2006, a set of 50 incandescent lights might cost $2.00 USD, while a similar set of 50 LED lights might cost $10.00 USD. The purchase cost can be even higher for single-color sets of LED lights with rare or recently-introduced colors, such as purple, pink or white. Regardless of the higher initial purchase price, the total cost of ownership for LED Christmas lights would eventually be lower than the TCO for similar incandescent Christmas lights[citation needed] since an LED requires much less power to output the same amount of light as a similar incandescent bulb. 
  •          LED phototherapy for acne using blue or red LEDs has been proven to significantly reduce acne over a 3 month period.[citation needed] as a medium quality voltage reference in electronic circuits. The forward voltage drop (e.g. about 1.7 V for a normal red LED) can be used instead of a Zener diode in low-voltage regulators. Although LED forward voltage is much more current-dependent than a good Zener, Zener diodes are not available below voltages of about 3 V. 
  •      Computers, for hard drive activity and power on. Some custom computers feature LED accent lighting to draw attention to a given component. Many computer manufactuers use LEDs to tell the user its current state. One example would be the Mac, which tells its user when it is asleep by fading the LED activity lights in and out, in and out.
  •          Lanterns 
  •          All these were appreciating the capacity of LED in new electronic devices, but LeeF uniquely sings songs of praise, as LEDs showed us the path to envisage the new trend and generation of lighting, the traditional incandescent equipped with a cluster of LEDs,
  •       We accentuated the real capability of LEDs to bring light to the world under maximum power saving conditions and mercury free environment…….


So be proud and say…LEDs are no more Light emitting diodes but LeeF Enlivened Diodes…

And it is with so much of pleasure that the LeeF company wishes the LED a happy 50th birthday…….

Saturday, September 15, 2012

Why we say YES to LEDS and NO to CFLS


Why we say YES to LEDS and NO to CFLS…just a simple clarification

It is said that LEDS are the new generation of lighting. LEDs are small, very efficient solid bulbs. New LED bulbs are grouped in clusters with diffuser lenses which have broadened the applications for LED use in the home. LED technology is advancing rapidly, with many new bulb styles available. Initially more expensive than CFLs, LEDs bring more value since they last longer. Also, the price of LED bulbs is going down each year as the manufacturing technology continues to improve.
A significant feature of LEDs is that the light is directional, as opposed to incandescent bulbs which spread the light more spherically. This is an advantage with recessed lighting or under-cabinet lighting, but it is a disadvantage for table lamps. New LED bulb designs address the directional limitation by using diffuser lenses and reflectors to disperse the light more like an incandescent bulb. But many do not like enter into the industry due to the high bargaining power of suppliers where they dominate with the high manufacturing cost of LEDS. But due to the latest technology it is said that day by day new models are produced and this has brought down the price of a tiny LED bulb down and eventually the entire manufacturing cost of a bulb that is made with a cluster of LEDS.
With all these features in mind it is pretty obvious that LEDS can provide you with a better lighting effect than CFLS do. Just to verify the point to our assenters more let’s distinguish the features between an LED and a CFL.
·         Long-lasting - LED bulbs last up to 10 times as long as compact fluorescents, and far longer than typical incandescent. So why ponder about the tiny discount we acquire buying a CFL over an LED.

·         Durable - since LEDs do not have a filament, they are not damaged under circumstances when a regular incandescent bulb would be broken. Because they are solid, LED bulbs hold up well to jarring and bumping.

·         Cool - these bulbs do not cause heat build-up. Common incandescent bulbs get hot and contribute to heat build-up in a room. LEDs prevent this heat build-up, thereby helping to reduce air conditioning costs in the home. New LED bulbs are available in 'cool' white light, which is ideal for task lighting, and 'warm' light commonly used for accent or small area lighting.

·         Mercury-free - no mercury is used in the manufacturing of LEDs. Mercury is a toxic metal associated with contamination of water, fish, and food supplies, and can lead to adverse health effects. A CFL bulb generally contains an average of 5 mg of mercury. You may be thinking that we are exaggerating, but just imagine; it is not a mere amount, but a hazardous amount of a toxic chemical that can evolve the whole eco system upside down, so why be responsible for a crime?
For further knowledge;
The mercury in compact fluorescent bulbs poses no threat while in the bulb, but if you break one:
- open a window and leave the room for 15 minutes or more
- use a wet rag to clean it up and put all of the pieces, and the rag, into a plastic bag
- place all materials in a second sealed plastic bag
- Wash your hands afterward.


·         More efficient - LED light bulbs use only 2-17 watts of electricity (1/3rd to 1/30th of Incandescent or CFL). LED bulbs used in fixtures inside the home save electricity, remain cool and save money on replacement costs since LED bulbs last so long. Small LED flashlight bulbs will extend battery life 10 to 15 times longer than with incandescent bulbs.

·         Cost-effective - although LEDs are initially expensive, the cost is recouped over time. LED bulb use was first adopted commercially, where maintenance and replacement costs are expensive. But the cost of new LED bulbs has gone down considerably in the last few years, continuing to go down. Today, there are many new LED light bulbs for use at domestic environment, and the cost is becoming less of an issue.

 Incandescent Watts
CFL Watts
LED Watts
Lumens (Brightness)
40
 60
 75 - 100
100
150
 8 - 12
13 - 18
18 - 22
23 -30
30 - 55
6 - 9
8 - 12.5
13+
16 - 20
25 - 28
400 - 500
650 - 900
1100 - 1750
1800+
2780

The above chart will give you a better understanding about the cost efficiency as well.
So with all these information, dear viewers there is no doubt in choosing an LED over a CFL. So why still say NO just because of its comparatively high price vis a vis a CFL.

Please be in touch with us for latest news of the next generation of LIGHTING……. 

Friday, September 7, 2012

An Invention that Changed the Mankind


An Invention that Changed  the Mankind
            We all are a part of an electrified world. Light bulb, particularly, profoundly revolutionized human existence. It not just helped in illuminating nights but also made human existence hospitable for an array of human activities. History of electric light, which adds to our daily convenience, bears testimony of many scientists, physicist’s efforts. But have we ever thought about how that the bulb developed up to today by time to time. Most of people know that it’s invented by Thomas Edison. But we have to know that they have done hundreds of experiments & try to achieve this objective. As we know Edison invented it, but there were few people who have took a step forward in this field before him. James Lindsay, Frederick Moleyns, Heinrich Göbel, Humphrey Davy and Warren Rue and are few of them.
            It was as early as 1809 when the foundation of the concept of light bulb was formulated. The history of light bulb is listed below in a brief yet concrete manner to truly explain the evolution of a mere idea to a common light bulb being use today.
            In 1809 and English chemist Sir Humphrey Davy made the invention of the electric luminosity. It was a simple experiment, which constituted a battery connected by the aid of two wires with a charcoal strip at the wire ends. This in history was the first glowing lamp. This method was overshadowed in 1820 when a scientist by the name of Warren De la made a lamp design making use of platinum coil in an evacuated tube and passing electrical energy through it. In 1835 James Bowman Lindsay presented a prototype light bulb, which was perhaps lost in the invention of the first electrical incandescent arc lamp, which made use of charcoal filament. The credit of this evolution goes to Edward Shepard who made the invention in 1850.
            1854 was the time when perhaps the true form of the light bulb was introduce in the world by a German watchmakers Henricg Globel. By using his innovative imagination he made use of bamboo strand inside a flute bulb. This concept was further modified in 1875 when Herman Sprengel originated mercury vacuum pump for a convenient light tuber. The time span from 1878 to 1880 saw many remarkable discoveries such as the use of long lasting electric light bulb in 1878 by Sir Joseph Wilson while at the same time Edison was working on constant betterment of light bulb and came up with a bamboo derived filament in 1880 which lasted for an incredible 1200 hours.
            A remarkable evolution took place in early 1906 when the general electrical company became the first company to officially patent a technique of making tungsten strand for light bulbs. The history of light bulb was on a roll their own many companies came in and scientist continues to embark on new techniques for constant improvements. In 1921 the first frosted light bulbs were introduced. In 1991 Philips invented light bulb lasting more than 60,000 hours.
            Now bulbs have come a long way and scientists are working to offer power saving, efficient and environment savvy bulbs. CFLS and LED bulbs are replacing the incandescent bulbs. Though a little costlier, they are environment friendly and power saving. Incandescent bulbs can be reasonably characterized just as heater that produces lights. As the typical incandescent offers only 3-5% light of the total energy it takes up. Remaining energy is wasted as heat. CFLs on the other side employ 75% lesser energy in the comparison and lasts 10 times longer. Useful long life and efficiency is adding to the popularity of CFLs.
            LED is also used by a lot of people and is more energy efficient than CFLs too. Standard LED offers around 35 lumens of light per watt as compared to around 12 lumen offered by an incandescent bulb. LED bulbs are getting developed and soon they would offer 131 lumens every watt. LEDs are used at a lot of places. These are used in trail lights of trucks and cars, watch dials, digital clocks, traffic signals, Christmas lights. Long life and durability has made it popular these days. It has become an ideal lighting for homes. One can find a range of LED bulbs in the market.

            From simple light bulbs to CFLs and LEDs, bulbs have covered a long way. Hardly did we know that small thing like bulb can literally illuminate our lives.

Why choose LeeF ?


Why choose LeeF ?

Prime focus on Quality
We provide you with solutions only if we are convinced on them ourselves. We ensure with experts that our products are of optimum quality achievable.

Engineers are us  
Engineering influences all processes and smart engineering application is a key to any successful organization. It gives us the unique opportunity to serve you. Yet engineering is not our business, it’s our passion. All our engineers are at LeeF to pursue their ambition to improve Sri Lankan engineering.

We cater for your need
Engineering solutions are not generic. They differ depending on the scenario. Therefore we provide solutions not specific products. We believe in fulfilling your need fully, without arising a new set of needs as a result of a solution.

We believe in strong relationships
Handling new technology is tricky, especially when technology is a secondary driving force to your household or your organization. We know that and we do not take you on the ride. We give you the whole picture, both pros and cons of a solution.
We believe in integrity and honesty in our core. We want to build the trust to ensure our association will last for years where you would be constantly updated with relevant new technologies.

Managing Directors Message

Managing Directors Message

Foreseeing the Future
LeeF’s value not just lies in its core of technology. As an innovation inspired company, I firmly believe that we are a competitive force for change. We initiate into big growth themes, ones that are critical to the national development and to the improvement for quality of life. We consider “growth” as a process led through innovation, customer centricity and integration of technology and design.
Our Company is led by the precepts that we must lead by being listeners and thinkers. Our members constantly occupy in realizing dreams, manipulating technology, revolutionizing the common thinking and redefining the rules of the game. They have all individually established themselves by deconstructing the established norms, by innovating beyond the conventional and by believing in the principle that Sri Lanka can be world-class.
I, as the Chief Executive Officer, am a believer in the power of technology, feasibility and long-term thinking. It is vision and the penchant for greatness that drove me to such bold initiation and Lead you to this path hidden from the general cycle of life. In life I have constantly gone against the grain and the conventional wisdom in pursuit of what I believe. Mine were not all successes but the failures lent to me greater wisdom and experience and the knowledge that from every failure I could recuperate a new beginning. Our brainchild LeeF is one such beginning.

Now is the time for us to serve Sri Lanka
As novices to corporate world we need to seize the opportunities and push the boundaries in realizing our vision. The potential is there, it is how we tap the opportunities to release that latent potential which will determine our pace of business success.
As citizens of Sri Lanka we need to think beyond our individual confines and objectives, collectively we must map an ambitious path for progress while driving Sri Lankan engineering from the forefront. It is most unrealistic and unlikely the journey will be unchallenged and unhindered, however, the visions we all collectively built were not mere words and an open mind, a realistic approach and optimism will, I believe will take us there.
Our expectations for LeeF are many. We envision it to be the future sustainable energy central player of Sri Lanka and one of the key catalysts in infusing a craving for novelty and consciousness for sustainability. Tough minded optimism and lifelong commitment to push the limits will drive our desire to create a giant that will chart a new course for Sri Lanka.
To my sincere shareholders and stakeholders, I call on all of you, to join hands with me on this journey. The future we foresee starts here. The passion for our profession will drive us there. The dreams we share will shape the course. The debt to our country we will repay.

P.D.R. Akalanka
Managing Director
31st March 2012