SPECIFICATION:Operation Voltage: 3VBattery: AAA battery, 1.5*2pcsWave Length: 532nmOutput: <30mw, CLASS IIIB Laser ProductOperating Temp Range: 15~30Storage Temp Range: -10~30
Simply press the Laser Beam Button to drive the laser pointer; at the same time, turning the cap, laser beam will emit directly from the Laser Output Aperture. You will see sparkling stars change variously in the sky
http://www.beamq.com/green-laser-pointers-emit-stars-p-90.html
2008-08-20
2008-08-18
Laser Pointers
Background
The laser pointer is a low cost portable laser that can be carried in the hand. It is designed for use during presentations to point out areas of the slide or picture being presented, replacing a hand held wooden stick or extendable metal pointer. It is superior over older pointers because it can be used from several hundred feet away in a darkened area and because it produces a bright spot of light precisely where the user desires. It has also caught on as an all-purpose pointing tool and has become so commonplace that laws have been passed to restrict its use.
History
Technically, the word laser is an acronym that stands for "light amplification by stimulated emission of radiation," but the term has become so commonly used that it is no longer capitalized. The radiation is the light that is emitted from the laser; this light can be visible or invisible to the human eye. Technically, only some lasers use light amplification, but the name laser is still used for a device that produces monochromatic (all one color or wavelength), coherent (the light waves are similar enough to move in one direction) radiation.
All lasers have a lasing medium, a source of energy, and a resonator. The lasing medium is a material that can be pumped (energized) by an energy source (such as light or electricity) to a higher energy state. After being pumped, the lasing medium can release that energy as monochromatic radiation. The resonator is an area that allows the released energy to build up before being released. A basic resonator is a pair of mirrors at either end of the lasing medium. One mirror is completely reflective so that all light striking it reflects back into the lasing medium; the other is partially reflective so that some of the light striking it reflects back into the lasing medium and some of the light passes through it to exit the laser. The pair of mirrors causes the light to reflect back-and-forth through the lasing medium and align itself in one direction, which produces the coherency of the light.
The theory used to produce lasers was published in 1958 by researchers at Bell Labs. The first laser, built in 1960 at Hughes Aircraft, used a piece of ruby for a lasing medium, light for an energy source, and mirrors to produce a resonator. The semiconductor laser was invented in 1962. It used a semiconductor material, similar to the materials used in transistors and integrated circuits for a lasing medium. It also used direct current (DC) electricity, the current produced by batteries, for an energy source. It still used resonator mirrors. The first semiconductor lasers produced non-visible infrared radiation. Current semiconductor lasers can also produce visible light, with red being the least expensive type of semiconductor laser and green, blue, and violet being increasingly more expensive. Semiconductor lasers used in laser pointers are also known as diode lasers, because they are a type of semiconductor diode. A diode passes electricity easily in one direction; light emitting diodes and laser diodes produce light when electricity passes through them. Semiconductor electronics have become less expensive to produce since the late 1950s. They have also become smaller and require less energy. They became inexpensive enough to be used in consumer electronic devices such as laser pointers in the 1980s. Current laser diodes are the size of a blood cell. They produce light that is less collimated (moving all in one direction) than most lasers because the shortness of the resonator space. Because of this, they need some sort of external optics (lenses) to focus the light into a tighter beam. Laser diodes, like many semiconductor devices, are delicate and need to be protected from the environment and from power surges. Power control circuitry, which usually includes a photodiode (a diode that produces electricity when light strikes it) to monitor the output of the laser diode, prevents the diode from receiving too much or too little power. The diode is protected from the environment by a plastic case so that is resembles most other semiconductor devices that are used on circuit boards.
The first laser pointers cost hundreds of dollars, but the demand and improved methods of fabrication have resulted in a price below five dollars for the most inexpensive types. There are also several items which incorporate laser pointers, or at least the components, such as laser sights for guns and projectors with built-in laser pointers.
Raw Materials
A laser diode is less complicated than many types of consumer electronic equipment. It consists of a laser diode, a circuit board, a case, optics, and a case. Some of the electrical components on the circuit board and the laser diode are made of semiconductor materials, metals, and ceramics. The semiconductor materials include compounds (materials made of more than one pure element) made of aluminum, gallium, arsenic, phosphorus, indium, and similar elements. These compounds are used in a variety of semiconductor products. Semiconductors also contain metals such as aluminum, gold, and tantalum.
The circuit board is typically made of a resin (plastic) such as epoxy with glass fibers in it to strengthen it. Electricity is conducted to the various components on the circuit board with lines of metal such as aluminum and copper. Individual components placed on the circuit board include diodes, the laser diode, capacitors, and resistors. Semiconductor parts, such as the diodes are encapsulated in plastic with metal leads that are connected to metal pads on the circuit board with solder (a metal alloy traditionally made of tin and lead, but now containing less lead and other metals as substitutes). Non-semiconductor parts, such as resistors and capacitors, are made of a variety of metals, plastics, and ceramics (including glass).
The collimating optics can be glass, but less expensive acrylic plastics are used in most laser pointers. The case can be made of any material, such as metal, plastic, or even wood. It contains metal (usually brass) contacts for the batteries.
Design
The design of the laser pointer depends on the electrical requirements of the laser diode, the desired lifetime of the power supply, and the drive to produce smaller consumer products. The smallest laser pointers are less than two inches in length, but some laser pointers are designed to look like pens. The longer laser pointers can hold AAA or AA batteries, which provide a longer lasting power supply than the watch batteries used in the shorter laser pointers. Most laser pointers use two or three batteries.
The ManufacturingProcess
The red laser pointer is the most common laser pointer. Other laser pointers use different laser diode assemblies, but are produced in a similar fashion, so the red laser pointer manufacturing process and diagram are used in this article.
The laser diode
The laser diode is produced in a semiconductor fab (a factory where semiconductor materials are produced in very clean and carefully controlled conditions). The substrate is the base material on which other materials will be deposited. A wafer of the substrate is produced, cleaned, and prepared. Then it goes through several steps where layers of material are deposited on it. Some of these layers are only several atoms thick. These layers can be conductive (metals such as aluminum and gold) or semiconductors (as described above). These layers can also be altered by exposure to other chemicals. After all materials are added to the wafer, it is diced (cut apart, usually into rectangular sections) into individual diodes. The diodes are tested either on the wafer or after separation, and nonfunctioning ones are scrapped (thrown away). Working laser diodes are then packaged in a plastic container with metal leads for electrical connection.
The circuit board
The circuit board contains the circuitry that makes the laser pointer function. It contains the switch, the laser diode, and the components of the control circuitry, typically a photodiode, diodes, resistors, and capacitors. These parts are placed on the circuit board, sometimes with an adhesive, and then are soldered in place. Soldering is a process where two metal objects are placed in contact and solder is melted around them so that when it cools, it surrounds both of them and holds them together. Solder is used instead of glue because it sticks to metal and because it conducts heat and electricity.
The collimating optics
The collimating optics in a laser pointer consist of a single lens that focuses the cone of light exiting the laser diode into a narrower beam that produces a narrower spot over a longer distance. Plastic lenses are injection molded, a process wherein molten plastic is forced into a mold. The plastic cools and solidifies, then the mold is pulled apart and the lens is removed. It is ground and polished to a smooth surface so that the light from the laser diode will not bounce off of imperfections on the surface.
The laser diode assembly
The laser diode and the collimating optics are put together with a plastic holder to form the laser diode assembly. Most laser diode assemblies have a metal spring attached at the back. This spring makes contact with the batteries in the laser diode and is part of the circuit that draws electricity from the batteries.
Case construction and finalassembly
The case is a tube with space for the laser diode assembly and the batteries. The laser diode assembly is pushed or screwed into one end of the case. The interior of the case is made of brass or has a brass strip (glued or riveted in place) running down the battery space. The battery space end piece also has an exposed brass area or is made of brass. When this end piece is pushed or screwed into the case, it contacts the other side of the batteries to complete the electrical circuit that allows electricity to flow from the batteries to the laser diode assembly.
The case also has a switch button (a piece of plastic sticking through a hole cut in the side of the case) that must be pushed and held for the laser pointer to work. When this button is pushed, the switch on the circuit board closes, electricity flows from the batteries to the laser pointer assembly, and the laser pointer produces a beam of light.
After the laser pointer is assembled and tested, a safety label is added. This label describes the rating of the laser in terms of power output, notes which regulations govern its use, and warns the user to avoid direct eye exposure.
Quality Control
A semiconductor manufacturer uses highly controlled processes that have been developed in laboratories and then transferred to the fabrication facility. Laser diodes are tested to make sure that they work after fabrication as well. Each other component is also tested to make sure that it works. Most manufacturing facilities will randomly test their products and use statistical control methods to provide quality products.
When the laser diode assembly or the laser pointer is finally assembled it will be powered and tested with a light detecting device, such as a photodiode, to measure its power output. Laser pointers are Type IIIA laser devices and must produce 5 mW (milliwatt, one thousandth of a watt) of power or less for the United States market. Laser pointers for the European market are typically Class II laser devices and must produce less than 1 mW. These restrictions are for safety purposes.
Byproducts/Waste
Laser pointers contain metals, plastics, and electronic parts. Each of those industries has specific waste byproducts (solvents, halocarbon gases, lead, chemicals), but laser pointer assembly has no specific wastes until the laser pointer is disposed of. A laser pointer contains small amounts of hazardous materials, such as lead and some toxic semiconductors. Like other electronic assemblies, it may be safer for the environment in the long term to recycle the components, though this is expensive and there are few programs in place to recycle or reuse electronics. This may change in the future.
The Future
Red laser pointers are the least expensive and most common today. Green laser pointers have more complicated laser diode assemblies and cost hundreds of dollars. Blue and violet laser pointers will be available soon at a higher price. Newer laser diode types come down in price as production volumes increase in order to keep up with demand, and as production processes improve. Laws that restrict laser pointer use may counteract this trend by causing a drop in demand as laser pointers are banned from public places.
Where to Learn More
Books
Gibilisco, Stan. Understanding Lasers. Blue Ridge Summit, PA: Tab Books, Inc., 1989.
Other
http://www.beamq.com/page.html?chapter=10&id=14
The laser pointer is a low cost portable laser that can be carried in the hand. It is designed for use during presentations to point out areas of the slide or picture being presented, replacing a hand held wooden stick or extendable metal pointer. It is superior over older pointers because it can be used from several hundred feet away in a darkened area and because it produces a bright spot of light precisely where the user desires. It has also caught on as an all-purpose pointing tool and has become so commonplace that laws have been passed to restrict its use.
History
Technically, the word laser is an acronym that stands for "light amplification by stimulated emission of radiation," but the term has become so commonly used that it is no longer capitalized. The radiation is the light that is emitted from the laser; this light can be visible or invisible to the human eye. Technically, only some lasers use light amplification, but the name laser is still used for a device that produces monochromatic (all one color or wavelength), coherent (the light waves are similar enough to move in one direction) radiation.
All lasers have a lasing medium, a source of energy, and a resonator. The lasing medium is a material that can be pumped (energized) by an energy source (such as light or electricity) to a higher energy state. After being pumped, the lasing medium can release that energy as monochromatic radiation. The resonator is an area that allows the released energy to build up before being released. A basic resonator is a pair of mirrors at either end of the lasing medium. One mirror is completely reflective so that all light striking it reflects back into the lasing medium; the other is partially reflective so that some of the light striking it reflects back into the lasing medium and some of the light passes through it to exit the laser. The pair of mirrors causes the light to reflect back-and-forth through the lasing medium and align itself in one direction, which produces the coherency of the light.
The theory used to produce lasers was published in 1958 by researchers at Bell Labs. The first laser, built in 1960 at Hughes Aircraft, used a piece of ruby for a lasing medium, light for an energy source, and mirrors to produce a resonator. The semiconductor laser was invented in 1962. It used a semiconductor material, similar to the materials used in transistors and integrated circuits for a lasing medium. It also used direct current (DC) electricity, the current produced by batteries, for an energy source. It still used resonator mirrors. The first semiconductor lasers produced non-visible infrared radiation. Current semiconductor lasers can also produce visible light, with red being the least expensive type of semiconductor laser and green, blue, and violet being increasingly more expensive. Semiconductor lasers used in laser pointers are also known as diode lasers, because they are a type of semiconductor diode. A diode passes electricity easily in one direction; light emitting diodes and laser diodes produce light when electricity passes through them. Semiconductor electronics have become less expensive to produce since the late 1950s. They have also become smaller and require less energy. They became inexpensive enough to be used in consumer electronic devices such as laser pointers in the 1980s. Current laser diodes are the size of a blood cell. They produce light that is less collimated (moving all in one direction) than most lasers because the shortness of the resonator space. Because of this, they need some sort of external optics (lenses) to focus the light into a tighter beam. Laser diodes, like many semiconductor devices, are delicate and need to be protected from the environment and from power surges. Power control circuitry, which usually includes a photodiode (a diode that produces electricity when light strikes it) to monitor the output of the laser diode, prevents the diode from receiving too much or too little power. The diode is protected from the environment by a plastic case so that is resembles most other semiconductor devices that are used on circuit boards.
The first laser pointers cost hundreds of dollars, but the demand and improved methods of fabrication have resulted in a price below five dollars for the most inexpensive types. There are also several items which incorporate laser pointers, or at least the components, such as laser sights for guns and projectors with built-in laser pointers.
Raw Materials
A laser diode is less complicated than many types of consumer electronic equipment. It consists of a laser diode, a circuit board, a case, optics, and a case. Some of the electrical components on the circuit board and the laser diode are made of semiconductor materials, metals, and ceramics. The semiconductor materials include compounds (materials made of more than one pure element) made of aluminum, gallium, arsenic, phosphorus, indium, and similar elements. These compounds are used in a variety of semiconductor products. Semiconductors also contain metals such as aluminum, gold, and tantalum.
The circuit board is typically made of a resin (plastic) such as epoxy with glass fibers in it to strengthen it. Electricity is conducted to the various components on the circuit board with lines of metal such as aluminum and copper. Individual components placed on the circuit board include diodes, the laser diode, capacitors, and resistors. Semiconductor parts, such as the diodes are encapsulated in plastic with metal leads that are connected to metal pads on the circuit board with solder (a metal alloy traditionally made of tin and lead, but now containing less lead and other metals as substitutes). Non-semiconductor parts, such as resistors and capacitors, are made of a variety of metals, plastics, and ceramics (including glass).
The collimating optics can be glass, but less expensive acrylic plastics are used in most laser pointers. The case can be made of any material, such as metal, plastic, or even wood. It contains metal (usually brass) contacts for the batteries.
Design
The design of the laser pointer depends on the electrical requirements of the laser diode, the desired lifetime of the power supply, and the drive to produce smaller consumer products. The smallest laser pointers are less than two inches in length, but some laser pointers are designed to look like pens. The longer laser pointers can hold AAA or AA batteries, which provide a longer lasting power supply than the watch batteries used in the shorter laser pointers. Most laser pointers use two or three batteries.
The ManufacturingProcess
The red laser pointer is the most common laser pointer. Other laser pointers use different laser diode assemblies, but are produced in a similar fashion, so the red laser pointer manufacturing process and diagram are used in this article.
The laser diode
The laser diode is produced in a semiconductor fab (a factory where semiconductor materials are produced in very clean and carefully controlled conditions). The substrate is the base material on which other materials will be deposited. A wafer of the substrate is produced, cleaned, and prepared. Then it goes through several steps where layers of material are deposited on it. Some of these layers are only several atoms thick. These layers can be conductive (metals such as aluminum and gold) or semiconductors (as described above). These layers can also be altered by exposure to other chemicals. After all materials are added to the wafer, it is diced (cut apart, usually into rectangular sections) into individual diodes. The diodes are tested either on the wafer or after separation, and nonfunctioning ones are scrapped (thrown away). Working laser diodes are then packaged in a plastic container with metal leads for electrical connection.
The circuit board
The circuit board contains the circuitry that makes the laser pointer function. It contains the switch, the laser diode, and the components of the control circuitry, typically a photodiode, diodes, resistors, and capacitors. These parts are placed on the circuit board, sometimes with an adhesive, and then are soldered in place. Soldering is a process where two metal objects are placed in contact and solder is melted around them so that when it cools, it surrounds both of them and holds them together. Solder is used instead of glue because it sticks to metal and because it conducts heat and electricity.
The collimating optics
The collimating optics in a laser pointer consist of a single lens that focuses the cone of light exiting the laser diode into a narrower beam that produces a narrower spot over a longer distance. Plastic lenses are injection molded, a process wherein molten plastic is forced into a mold. The plastic cools and solidifies, then the mold is pulled apart and the lens is removed. It is ground and polished to a smooth surface so that the light from the laser diode will not bounce off of imperfections on the surface.
The laser diode assembly
The laser diode and the collimating optics are put together with a plastic holder to form the laser diode assembly. Most laser diode assemblies have a metal spring attached at the back. This spring makes contact with the batteries in the laser diode and is part of the circuit that draws electricity from the batteries.
Case construction and finalassembly
The case is a tube with space for the laser diode assembly and the batteries. The laser diode assembly is pushed or screwed into one end of the case. The interior of the case is made of brass or has a brass strip (glued or riveted in place) running down the battery space. The battery space end piece also has an exposed brass area or is made of brass. When this end piece is pushed or screwed into the case, it contacts the other side of the batteries to complete the electrical circuit that allows electricity to flow from the batteries to the laser diode assembly.
The case also has a switch button (a piece of plastic sticking through a hole cut in the side of the case) that must be pushed and held for the laser pointer to work. When this button is pushed, the switch on the circuit board closes, electricity flows from the batteries to the laser pointer assembly, and the laser pointer produces a beam of light.
After the laser pointer is assembled and tested, a safety label is added. This label describes the rating of the laser in terms of power output, notes which regulations govern its use, and warns the user to avoid direct eye exposure.
Quality Control
A semiconductor manufacturer uses highly controlled processes that have been developed in laboratories and then transferred to the fabrication facility. Laser diodes are tested to make sure that they work after fabrication as well. Each other component is also tested to make sure that it works. Most manufacturing facilities will randomly test their products and use statistical control methods to provide quality products.
When the laser diode assembly or the laser pointer is finally assembled it will be powered and tested with a light detecting device, such as a photodiode, to measure its power output. Laser pointers are Type IIIA laser devices and must produce 5 mW (milliwatt, one thousandth of a watt) of power or less for the United States market. Laser pointers for the European market are typically Class II laser devices and must produce less than 1 mW. These restrictions are for safety purposes.
Byproducts/Waste
Laser pointers contain metals, plastics, and electronic parts. Each of those industries has specific waste byproducts (solvents, halocarbon gases, lead, chemicals), but laser pointer assembly has no specific wastes until the laser pointer is disposed of. A laser pointer contains small amounts of hazardous materials, such as lead and some toxic semiconductors. Like other electronic assemblies, it may be safer for the environment in the long term to recycle the components, though this is expensive and there are few programs in place to recycle or reuse electronics. This may change in the future.
The Future
Red laser pointers are the least expensive and most common today. Green laser pointers have more complicated laser diode assemblies and cost hundreds of dollars. Blue and violet laser pointers will be available soon at a higher price. Newer laser diode types come down in price as production volumes increase in order to keep up with demand, and as production processes improve. Laws that restrict laser pointer use may counteract this trend by causing a drop in demand as laser pointers are banned from public places.
Where to Learn More
Books
Gibilisco, Stan. Understanding Lasers. Blue Ridge Summit, PA: Tab Books, Inc., 1989.
Other
http://www.beamq.com/page.html?chapter=10&id=14
2008-08-14
2008-08-12
50mW 532nm Green Laser with Black color
Produce clearly visible green beam in the daytime. These lasers are not toys and have a range of up to 10 miles you not only see the green dot you also can see the beam. Great for hiking ,pointing out stars,they really are great fun but must be used with great care.
100% Brand New Professional green laser pointer pen Utilizing the latest technology in green laser
Color: Rubber blackMaterial: AluminumDimensions: 145mm(L) x 11mm(Diameter) Class: IIIB Wavelength: 532nmOutput Power: 50mWOutput Mode: Constant Wave Operation: ON/OFF touching buttonProject distance : 25000feet away (less in daylight).Battery: Alkaline AAA x 2pcs(not included as oversea shipping)Battery Life: 6 hoursDot Size: 15*15mm at 10M distanceExpected Life: 5,000 hours Package : EVA+Paper box, or Tin box with EVAGift Case Included
WARNING: Never point at people and always avoid direct eye contact.
100% Brand New Professional green laser pointer pen Utilizing the latest technology in green laser
Color: Rubber blackMaterial: AluminumDimensions: 145mm(L) x 11mm(Diameter) Class: IIIB Wavelength: 532nmOutput Power: 50mWOutput Mode: Constant Wave Operation: ON/OFF touching buttonProject distance : 25000feet away (less in daylight).Battery: Alkaline AAA x 2pcs(not included as oversea shipping)Battery Life: 6 hoursDot Size: 15*15mm at 10M distanceExpected Life: 5,000 hours Package : EVA+Paper box, or Tin box with EVAGift Case Included
WARNING: Never point at people and always avoid direct eye contact.
Green/Red Laser Pointer
Battery Installation:Unscrew the end cap and insert 2 x N sized batteries with the positive end outward. Operation:Point the desired laser away from you and press the green or red button and hold to turn the laser on. When you release the button it will turn the laser off.Specifications:Complies with 21 CFR 1040.10 & 1040.11 Accession #9812316-00Wavelength 650nm(Red) and 532nm(Green)Output Mode-Constant WaveOutput power<1mw(Red) and < 5mw(Green)Operating lifetime 8000 hours(Red) 4000 hours(Green)Range 4000 ft(Red) and 10000 ft(Green)Batteries 2 x N cell batteriesDimensions 7 inches in length , 1/2 inch diameter
Safety Precautions:Direct eye contact with laser beam may cause eye injury and should be avoided.Use of controls or adjustments or performance of procedures other than specified herein may result in hazardous radiation exposure
http://www.beamq.com/greenred-laser-pointer-p-88.html
Name:Green Light Laser Pointer
Name:Green Light Laser PointerDimension:diameter14 X 160mm Output Wavelength:532 nm Working Voltage:DC=3.0VTrigger Voltage:DC=2.3VWorking Current:I<250mAWorking Temperature:-20~+35Storage Temperature:-20~+60 Appearance and Color: Rubber Black(according to the request of customer) Parameter:Fixed focus, green dot facula, continuous output and working time over 5000 hours Output Power:5mW (1mW,10mW,15mW,20mW,30mW,50,80,100mW,150mW,200mW also for clients)
2008-08-04
100mw black green laser pointer
Introduction:Utilization of the latest laser crystal technology and optics creates this high quality;pen-sized Laser Pointer. It emits an intense, brilliant laser beam and has a range up to 1000 meters. Use your laser pointer to aim at any desired targets on projection screens,video monitors, presentation graphics, and any opaque as far as several hundred meters. Elegant gift box included.
User Safety Precautions:Under normal operation,it is safe to the human body.Focusing directly on a laser beam may result in temporary or permanent eye damage. Care should always be taken.
Battery Installation:When inserting the batteries ALWAYS point the laser emission hole away from your eye.Unscrew the pen clip from the pen. Insert batteries positive end upward and tightly screw the pen clip.Must use AAA size alkaline batteries.
Operation:Presss the push button to turn it on.Release the push button to shut if off automatically.Operating temperature: 15-35 degree.This pointer is not designed for long-term use.Constantly turning on will return accumulation of high temperature and sacrifice the lifetime of laser diode.
Caution:Never stare directly at the laser beam.Please keep out of reach of children.Do not drop the laser pointer on hard surface;it damages the pointer components and causes a malfunction.This high-end optic product must be handled with care.
Specifications:Wave length:532nmOutput Mode: Constant WaveOutput Power:100mw
CE FDA RoHs PAHs
http://www.beamq.com/100mw-black-green-laser-pointer-p-82.html
User Safety Precautions:Under normal operation,it is safe to the human body.Focusing directly on a laser beam may result in temporary or permanent eye damage. Care should always be taken.
Battery Installation:When inserting the batteries ALWAYS point the laser emission hole away from your eye.Unscrew the pen clip from the pen. Insert batteries positive end upward and tightly screw the pen clip.Must use AAA size alkaline batteries.
Operation:Presss the push button to turn it on.Release the push button to shut if off automatically.Operating temperature: 15-35 degree.This pointer is not designed for long-term use.Constantly turning on will return accumulation of high temperature and sacrifice the lifetime of laser diode.
Caution:Never stare directly at the laser beam.Please keep out of reach of children.Do not drop the laser pointer on hard surface;it damages the pointer components and causes a malfunction.This high-end optic product must be handled with care.
Specifications:Wave length:532nmOutput Mode: Constant WaveOutput Power:100mw
CE FDA RoHs PAHs
http://www.beamq.com/100mw-black-green-laser-pointer-p-82.html
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