Comparison of brightness of light spot and beam among lasers of different wavelengths
Comparison of brightness of light spot and beam among lasers of different wavelengths
Some beginners often ask me how much the power of 532nm laser equivalent to the brightness of 445nm laser is
The question may not be so easy to answer, because the sensitive degree of each eye to light of different wavelengths is not the same.
And the feelings will be also different in the dark and light conditions .
Scientists have established light / dark vision functions respectively according to the mean value of human vision in the light / dark environments.
When the brightness is more than 3cd/㎡, it is a photopic vision, and pyramidal cells play a major role, peak value of V(λ)will be between 550nm~560nm; when the brightness is less than 0.03cd/㎡, it is a scotopic vision, rod cells play a major role, peak value of V(λ)shifts to short wavelength, equivalent to blue green parts between 500~510nm. Functions with brightness between 3~0.03 also appear in this position.
First let’s discuss the spot brightness. Spot brightness is basically decided by visual function when the power and density are the same.
The function value of 532nm is very high both in light and dark conditions, so it has relatively high brightness.
While the function value of 445nm is quite different in light and dark conditions, theoretically, the brightness is very low in daytime and has a good effect in night.
But, in fact, we also need to consider the factor of the main light.
For example, observe spots in the sunlight.
This is the power distribution of sun light.
Spot brightness also depends on the difference value of light source.
Just like 445nm, it is in a depressed position of solar spectrum, so it has a obvious contrast that the brightness of observation under sunlight has improved.
Next, let’s talk about the beam brightness.
Beam brightness is not only related with vision function but also has a great relationship with the scattering rate.
Even when they have the same power and beam diameter, because the air scattering rate is not the same, their power density will be different.
Atmospheric scattering is divided into various types, some have a stronger scattering to short wave, while some have basically the same scattering to full waves.
So this has enhanced beam brightness of short wave like 445nm once again, but it has also increased the loss of distant 445nm beam, therefore, 445nm beam often looks bright up close and dark at a distance.
Finally, I would like to remind of the safety of yourselves and others.
Ensure that there is no any personnel near light path or new light path that may be generated by reflection.
We are not recommending to observe laser spot up close with naked eyes without any protection.
Bonding crystal, optical cement crystal, separated crystal
Bonding crystal, optical cement crystal, separated crystal
First introduce the principle of 532nm laser
808nm semiconductor laser diode (LD) of pumping source supplies energy to laser crystal
Most of crystals are Nd:YVO4, some are Nd:YAG, both have Nd3+ ions and can produce 1064nm infrared laser
Infrared laser turns into 532nm green light through KTP nonlinear frequency doubling crystal
So, 532nm has 2 crystals, including laser crystals and frequency doubling crystal, the combination method of these two crystals include bonding, optical cement and separation.
Bonding crystal. UV light adhesives are adopted to bond crystals. If the power is relatively large, the crystals will be heated up quickly, then that would be a tragic if adhesives may come unglued after expansion and contraction. The extreme power of agglutination crystal is 200mw and its stability is poor
Optical cement crystal. A special treatment is conducted to contact surface of crystals (estimated to be highly polished), then crystals will be pressed together, crystals after this treatment will not be easy to come unglued as molecular forces integrate and their stability are relatively high, good for lasers below 300mW
Separated crystal. 2 crystals are separately placed for independent cooling, it can withstand a great power. Its weaknesses is that complex adjustment is needed to change the crystal position to achieve the maximum output and it has complex structure, large volume and high cost.
Laser Spatial mode
Laser Spatial mode
The distribution of light intensity on cross section of laser beam is called laser transverse mode. The transverse mode is generally regarded as the laser mode. TEMmn is used to present transverse mode. TEM means transverse electromagnetic wave, both m and n are positive integers, respectively standing for ordinal numbers of the points with zero light intensity on x axis and y axis, called mode ordinal number. The diagram below shows light spots of several different laser beam transverse modes. TEM00 mode is also called as the basic mode, the light intensity of any point in its spot will not be zero. If there is a light intensity of any point in spot on x axis is zero, it is called as TEM10 mode; If a light intensity of any point in spot on y axis is zero, TEM01 mode, and so on, mode ordinal numbers m and n are larger, there are more points with zero light intensity in spots. Laser beam with different transverse modes is called as multimode.
Calculation method of laser divergence angle
Calculation method of laser divergence angle
Firstly, adjust the laser light to parallel light
to measure distant light spot and light spot at aperture
Divergence angle =2arctan ((spot diameter- beam diameter at aperture) / 2 / distance) * 1000All units are mm
For convenience’s sake, you can use the following simple formula
(spot diameter (mm) – beam diameter at aperture (mm))/ distance (m)
Note: the above formula adopts the radian calculation result, the unit is mrad, if using the angle calculation result, please take ×π/180 as the unit
If it is 445nm laser, as all spots are rectangular and have big divergence in ⊥ direction, the beam diameter at aperture is the short side to measure spots at aperture while the beam diameter at aperture is the long side, the same for 635nm laser
Introduction to the characteristics of laser pointers of various wavelengths (colors)
Some laser lovers often ask me which one is better between two lasers of different wavelengths
Here I would like to introduce the characteristics of hand-held lasers of various wavelengths
according to the order from short wave to long wave
Personal Recommendation
For those who like showing off the light beam but don’t want to burn things, I recommend laser 400MW 532nm, it is very bright and you won’t feel 1000mW laser will be much brighter than this.
For those who like to burn things and show off the light beam once in a while, I recommend laser 1.6W 445nm, it is awesome to burn things up close.
For those who like to burn things from a distance, I recommend laser 500MW 405nm, this is absolutely good for lighting matches within 10 meters with ease.
CivilLaser DPSS Lasers 405nm 457nm 473nm 515nm 520nm 532nm 561nm 589nm 607nm 637nm 671nm
CivilLaser DPSS Lasers 405nm 457nm 473nm 515nm 520nm 532nm 561nm 589nm 607nm 637nm 671nm
CivilLaser — Motorized Angle Stages|Optical Mounts tables holders mirror mounts| Multi-Axis combination stages
Motorized Angle Stages(Rotation and Tilt)
One-Axis Motorized Goniometer Stages
Two-Axis Motorized Gonimometer Stages
Two-Axis Motorized 360 Rotation Stages
Three Axis Motorized Goniometer and 360 Rotation Stage
Two-Axis Motorized Tilt Stages
Three-Axis Motorized Tilt and 360 Rotation Stage
Optical Mounts – Tables, Holders
Solid Plates
Protable Solid Plates
Optical Breadboards
Laser Tube Holders
Fiber Polarizers
Lens Holders
LIght Bafles
Heavy Duty Rod
Fine Ajustment Mounting Posts
Height Adjustable Moumting Posts
3-jaw Self-centering Chuck and Holder
Adjustable width Slits
Optical Mounts-Mirrow Mounts
2/3/4-Axis Linear Adjustment Mirror Mounts
Motorized Mirrow Mounts
Multi-Axis Compact Adjustment Stages
Optical Coupling modules
Laser Mounts
PrecisionPolarizer Mounts
Precision Polarizer Mounts
Multi-Axis Combination Stages
Most powerful blue laser pointer 445nm 3000mw laser — 2×16340 or 2×18650
Most powerful blue laser pointer 445nm 3000mw laser — 2×16340 or 2×18650
1. Battery installation method.
Never install 3 batteries; it will burn out the laser as quick as a flash.
If you brought this blue laser pointer from our web store, please according to the following standards, strictly regulate the use of:
The International Electrotechnical Commission (IEC): the establishment and management of international laser safety standards, IEC 60825-2007
American: America National Standards Association (ANSI) laser safety committee Z136-2000 standard
China:
A) Radiation safety of laser products: GB7247.1-2001
B) Safety standards of laser protection device: GB18151-2000
C) Laser safety standards: GB18217-2000
D) Safety standards of laser operation field: GB10435-1989
According to the classification of laser products (GB 7247.1-2001) standard, this product belongs to the class IV: even by the laser diffuse reflection also is likely to cause harm, will burn the skin, ignite flammable materials, you should be particularly careful when the user operates this kind of laser source.
The wavelength of this product is the 445NM, visible light (400nm-700nm) laser, and the impact on the eye mainly for the photochemical and thermal effects induced retinal injury, The main effects on the skin mainly as dark , light-sensitive effect, skin burns .
Continuous density laser irradiation eyes will cause irreversible damage, please exercise caution when in close use, and please wear protective goggles for protection.
When not in use, should be placed in the minors cannot get place, and remove the batteries, turn off the switch, twist out safety pin for safekeeping, to prevent accidental injury events.
Our purchasers to determine before buying, we have notification obligation, the buyer must be observed, if the buyer does not listen to advice all the consequences of what happened, borne by the buyer, the shop is not responsible.
In addition, the restaurant lasers prohibit the sale to minors, please note!
Blue 3W laser pointer Precautions
The blue 3W upgrade project description:
1. After the upgrade, the attack of head is the 316 stainless steel material, high hardness, sufficient for self-defence and emergency hit hard materials like glass or material under normal circumstances.
2. The laser module heat radiating area increased one-third compared with the blue 2W, the better ability of continuous working.
3. Added safety latch and switch contacts, safety pin made from the plastic material to copper nickel-plated contacts plus higher conductive properties of 24K gold.
4. Added the ignition position line, to help with quick guide to had not been exposed to laser products buyers.
Have to take practical action to optimize the product, so that customers buy products with more practical value in use and continuous improvement, we will continue to move forward, and strive to bring you better products, never negative the laser lover’s love.
The blue 3W instructions:
1: using a laser lamp, without prolonged tube with two short battery, positive towards the tail cover, short battery and long battery cannot mix, also cannot be loaded at the same time 4 short batteries, battery single voltage is 3.7V, the flashlight for 7.4V driver.
Add the extension tube to put two long battery, positive towards the tail cover, cannot hold two small batteries a large battery.
Note: If fault wrong battery lead, is not in the scope of free warranty.
2: the laser diode is a high fever components, overheating could cause the laser diode accelerated aging, affect the service life of the laser pointer, so we suggest that when the heating is better in your hand, close it and cooling it.
3: multi gear products with exclusive four grade, dimming mode, divided into strong, weak and slow, flash mode, all the stalls are with slow start protection, light way: open the flashlight quickly after pressing the switch two times, into the next gear, laser flashlight with memory model, closed hand electric five seconds later, open default reply to open before the stall next time.
4: the use of LED lighting lamp holder, an 18650 battery driver, LED lamp is negative, so the battery negative pole with laser instead, with the correct method is positive in spring, negative towards the tail cover.
LED flashlight, with strong, weak, in the flash, SOS five stalls, continuous press two can enter the next gear.
5: Prohibited dismantle laser pointer, otherwise there may void the warranty.
6: the prohibition by the human body, especially the eyes, any accidents such as buyers do not follow the instructions as a result, the shop will not bear any responsibility.
Most Powerful burning Green Laser pointer Instructions – 1 x 18650 battery
Most Powerful burning Green Laser pointer Instructions – 1 x 18650 battery
1. Battery installation method.
The anode point to the lid.
1 x 18650 battery (Not Include)
2. The use of attention
Do not continuous light the laser over 120 seconds, we advice you turn off the laser every 60 seconds when the room temperature is too high. This is a high power handheld laser pointer, large heat productivity but do not have the heat radiating device, long time lighting is easily burnt out laser tube, will cause the laser point does not light or faint light.
3. Security warning
★ Do not look at the laser directly.
★ Do not use laser irradiation of others.
★ Do not use laser irradiation the objects which is easy to reflect light.
★ Do not let a minor child touch laser pointer.
Charge Description:
When charging the red light is on, after charging full the signal light is green.
Charging time reference:
1. 18650 battery: About 6 hours;
Lithium battery using common knowledge:
1. Do not over charging, over discharge, or whatever the lithium battery once will be scrapped (remember not to reduce the service life, was scrapped)
2. Do not run out the battery power, when you find that the lights dimmed you need to charge. (Do not charge too long time, just full is the best 😉
3. Beware of the battery is shorted, because the battery is not set short-circuit protection can result in excessive heat, or explosion
4. Do not throw batteries into fire, otherwise it will explode.
日本語 使用注意
連続使用時間は120秒を超えないでください。室外の温度は高い時に60秒毎に閉じたほうがいいです。
これはレーザーポインターの高効率のハンディタイプです。高効率なので発熱が大きい、それにハンディタイプは放熱装置が配置されていないので、長時間使用とレーザーパイプが燃しやすい、レーザーポインターが点滅しないや光が微弱の問題が起こります。
安全警告
★ レザーを直視ないでください。
★ 他人にレザー照射をしないでください。
★ 反射し易いものにレザー照射をしないでください。
★ 未成年の子供をレーザーポインターに接触させないでください。