THE SHOW LASER LIGHT GUIDE

What laser do I use for my venue?

 

This mainly depends on the desired application of the laser system: - Beam show & aerial effects - Graphics projections - Indoor - Outdoor - Power and scanners (see Scan Speed & Angle ) are also important decisive factors.

For mobile DJs, home use and private parties, small bars etc, Laser systems with a total output power of up to 500mW are suitable in most cases. Lasers in a power range of 500mW to 1,500mW are good for small clubs and discos, 1,500mW to 5,000mW suit large nightclubs, discos and mid-sized events. Lasers with 5,000mW and up are used at large in and outdoor events, festivals, concerts etc.

 

 

Beams or graphics laser ? - Scan speed & angle

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The possible scan speed of a laser system depends on the scanning system. The speed is specified in pps (points per second) or kpps (kilo points per second). It describes how fast both mirrors of the scanning system can move and how fast they can deflect the beam. The higher the scan speed, the better and the smoother the laser beam, graphics. Important: The possible maximum scan speed depends on the actual scan angle. To project graphics it is recommended to at least have 25kpps @ 8° ILDA. Aerial or beam shows can be created with less speedy scanners as well. The range of Tarm lasers can be upgraded to faster scanners from the standard ones fitted, please see upgrade option on the shop product page

 

 

What is RGB ? - Modulated or TTL

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RGB lasers are show laser systems with exactly three colour modules: Red, Green and Blue. It doesn't matter if the colour sources are DPSS, OPSL or pure Diode laser modules. By combining the three colours, white light laser effects are possible. Please note modulation of a laser describes its ability to switch output on and off during drawing a pattern and to create colour mixture. Modulation can be TTL, which means the laser source can only switch on and off, but not dim, and can only provide up to 7 different colours shades. The other option is an analogue modulated laser, this will display up to 16,7 million different shades of colours depending on the ability of a laser source. Also, its possible to dim the output power of the laser beam.

 

Laser sources ? - DPSS, Pure diode & OPSL

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Modern show laser light systems use solid state or semiconductor laser sources: DPSS, pure diodes and OPSL. DPSS (diode pumped solid state) laser sources are mainly used in smaller laser systems, but special types are also used in very high end lasers. Diode sources have a good price-quality ratio and they are the most common laser sources. Diode-only, sometimes called pure diode laser systems are considered long-lasting and durable, due to the semiconductor technology of the diode sources. OPSL (optically pumped semiconductor laser) technology is used in high end laser projectors due to their great beam specifications.

 

 

What does the term (MRAD) mean ? -Beam specifications

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Laser beam specifications have two parameters: beam size (diameter) and beam divergence. The beam size specifies the width of the beam at aperture (mm), the beam divergence specifies the widening of the beam over distance (in mrad). The divergence is the most important factor. It also heavily influences the actual visibility of a laser after a certain distance. The smaller the divergence, the better, as the beam stays much tighter over distance.

 

Why are there two sets of numbers? - Laser power

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The total laser power respectively output power of a laser is the total result of all built-in laser sources. This power is measured in mW (milliwatts) or W (Watts). The power specification can be given before or after optics. Before means directly at the laser sources, after means measurement after the laser aperture. Values given after optics and after aperture already comprise power loss due to optical components. When purchasing a laser, look for the guaranteed power or after optics power to give you the idea of what laser power you will have available from the projector.

 

What is the term, NM ? - Wavelength

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The physical term 'Wavelength' determines the colour of a laser source and is specified in the unit nm (nanometer).

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The 655/650nm Red diode is easier in: Handling and its cheaper, although the beam profile is worse. These kind of diodes are normally not suitable for optically combining more than two single diodes, that's why the red power can be limited. This type of diode is used in budget systems and they have a very good price to performance-ratio. The red colour is also deeper.

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Professional diode laser systems are usually equipped with 638nm red diodes. These have a very good visible red colour and can be collimated to good beam shapes. The handling of these kind of diodes are quite tricky, especially if there is the need of combining more than two diodes. Laserworld use this diode type in their professional laser systems.

Most Chinese manufacturers are not able to handle this kind of diode

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What Blue colour is best visible - 405nm, 445nm or 473nm?

In terms of visibility, the nanometre values that are nearer to 550nm are better than values further away. 473nm is best visible. However, this colour is more Cyan than Blue, and thus cannot create a good royal Blue. In terms of colour spectrum, the 473nm is much worse than the 445nm. The 405nm Blue in contrast is nearly not visible and therefore needs a lot of power to become visible. As there is not much advantage (and even some disadvantages) compared with the colour spectrum of the 445nm, Laserworld decided to mainly feature the, as we think, optimum visibility - colour-range combination in our range of lasers.

 

Green Laser - solid state diodes usually come in 532 nm and diode pumped DPSS systems 561 nm

 

How do I control my laser?- Operation modes.

Most small laser projectors have an automatic or a sound-to-light mode, or both. When the automatic (stand-alone) mode is active, the show laser displays pre-set patterns automatically. If the (sound-to-light) mode is chosen, then the laser triggers beams according to the ambient noise or music. Many laser systems can also be controlled by DMX 512, where pre-programmed patterns can be selected with a DMX controller or DMX software. Lasers with ILDA mode can be controlled by laser show control software. Professional laser shows are controlled with ILDA software.

 

Grating Effect - What is it for?

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A grating effect is an optical deflection grid, that multiplies the input rays. E.g. if you shoot a single laser beam to the grating, you get a kind of star effect (burst grating) or a dotted line (line grating) on the other side. Every colour spectrum is deflected in a different way, so if you have a multi colour input, you get the colours split up as well. That's why it is physically not possible to generate a white star effect with the use of a deflection grating. Simple grating effects are used in the very common Star Effect Lasers, but also in more professional systems like the pro line series. Grating effects can also be used with mirrors (BURST-10, LIN-10)

 

Laser Class

 

Laser classes are specified according to IEC 60825-1:07-2015 :

Laser Class 2 Class 2 lasers emit only visible radiation not exceeding 1mW power. Accidentally looking into the beam does not create damage to the eye, even when using optical instruments. Warning: Looking into the beam intentionally may be dangerous (as the reflex of closing the eye or turning away is not working)!

 

Laser Class 2M Class 2M

lasers emit a visible beam (400-700nm), which is either widened or divergent. The limit for the whole beam is 500mW (limit for class 3b). The pupil cuts only a portion of the beam. This portion must not exceed the limit of class 2. When viewed with optical instruments class 2M lasers can be dangerous. Viewing with a loupe or a telescope/binocular can reverse the widening/divergence of the beam and thus exceed the limit for class 2. Glasses are not considered optical instruments in this regard. The manufacturer has to indicate which optical instruments can be dangerous.

 

Laser Class 3R

Class 3R emit a visible beam (400-700nm) that does not exceed 5 times the limit of class 1 for invisible, or 5 times the limit of class 2 for visible radiation (=5mW). R stands for relaxed, lasers of class 3R do not require the same safety measures as lasers of class 3b and 4 do. Warning: Class 3R lasers can damage the eye, even when only looking into the beam for a short time. Do not look into the beam! Laser

 

Class 3B

Lasers of class 3B emit in continuous wave mode a power of maximum 500mW. Direct viewing of the beam will cause damage to the eye! When viewing the image of the beam/spot on a diffuse reflecting wall, the eye will not be damaged. (Distance to the spot 13cm, viewing time less than 10sec.) Warning: Class 3B lasers can damage the eye, even when only looking into the beam or into specular reflections for a short time. Do not look into the beam!

 

Laser Class 4

All other lasers are class 4. There is no limit for class 4 lasers. Beam, specular reflections and diffuse reflections can very dangerous for both eyes and skin! When viewing diffuse reflections, the MPE level of the reflection has to be assessed. Class 4 lasers can damage eye and skin by direct or indirect radiation! The radiation of class 4 lasers can release toxic fumes from certain materials and ignite inflammable or explosive materials.

 

Do I need any special knowledge for operating a show laser display?

 

In general there is no deeper knowledge necessary to operate a laser projector in a physical sense. However, laser light may be quite dangerous if it is not properly used. Due to the coherence of the laser light (same direction and wave characteristics of the light - different to normal light sources), the very sharp rays can be dangerous to the human eye or imaging sensors. However, if you respect your local laser safety regulations, it is possible to make a safe laser show.

The regulation IEC 60825-1 is internationally valid and provides information about laser safety terms. Most countries refer to that regulation in context of laser safety. However, some countries may have more fear of the dangers involved with this type of light source and thus may have stricter regulations.

 

THE UK REGULATIONS PLEASE REFER TO PLASA - Guidance for the Safety of Display Lasers.

This guidance is based on much of the material that HSE originally used in HS(G)95, that was made available to PLASA to assist in preparing the industry guidance. Following the guidance is not compulsory, and you are free to take other action. PLASA however states that if you do follow the guidance you are probably doing enough to comply with the law.

 

RESPONSIBILITIES

The responsibility for laser operation is with the actual operator. So being careful is very important. Some things we recommend to respect: Never shoot single beams to the audience. You may shoot them above their heads (min height 3m) as strong as you like. Use a safety shut-off option (button etc.) to be able to switch of the system, e.g. if somebody tries to manipulate the lasers during operation or if somebody enters the laser safety area. Keep people under age away from laser devices. Familiarise yourself with laser safety prior to operation. Some Events will require a Risk assessment and a Laser Safety Officer on site during operation. laser lighting display can be a fantastic and memorable addition to a performance and/or event. If the display involves the use of hazardous lasers with high radiant powers (typically from 200mW to 40W+ ie class 3B &4 lasers) then action will be required to control the risk of a significant eye injury. High power lasers with radiant powers that exceed around 500mW may also burn skin on contact and can be a fire risk. Other hazards include outdoor laser display beams dazzling passing motorists, pilots etc.

Laser projectors are not dangerous themselves - the danger always comes from