Series of Laser Machine

Laser machining

Laser machining is material removal accomplished by laser material interaction, generally speaking, these processes include laser drilling, laser cutting and laser grooving, marking or scribing.

Laser cutting

Laser cutting works by directing the output of a high-power laser, by computer, at the material to be cut. The material then either melts, burns, vaporizes away, or is blown away by a jet of gas,[1] leaving an edge with a high-quality surface finish. Industrial laser cutters are used to cut flat-sheet material as well as structural and piping materials.

Laser marking

laser marking, is the practice of using lasers to engrave or mark an object. The technique does not involve the use of inks, nor does it involve tool bits which contact the engraving surface and wear out.

Laser welding

Laser welding  is a welding technique used to join multiple pieces of metal through the use of a laser. The beam provides a concentrated heat source, allowing for narrow, deep welds and high welding rates. The process is frequently used in high volume applications, such as in the automotive industry.

Laser drilling

Laser drilling of cylindrical holes generally occurs through melting and vaporization (also referred to as "ablation") of the workpiece material through absorption of energy from a focused laser beam..

Type of Laser

Solid state laser

Solid-state lasers operate at wavelengths on the order of 1 micrometer, much shorter than gas lasers, and as a result require that operators wear special eyewear or use special screens to prevent retina damage. Nd:YAG lasers can operate in both pulsed and continuous mode, but the other types are limited to pulsed mode. The original and still popular solid-state design is a single crystal shaped as a rod approximately 20 mm in diameter and 200 mm long, and the ends are ground flat. This rod is surrounded by a flash tube containing xenon or krypton. When flashed, a pulse of light lasting about two milliseconds is emitted by the laser. Disk shaped crystals are growing in popularity in the industry, and flashlamps are giving way to diodes due to their high efficiency. Typical power output for ruby lasers is 10–20 W, while the Nd:YAG laser outputs between 0.04–6,000 W. To deliver the laser beam to the weld area, fiber optics are usually employed.

Gas laser

Gas lasers use high-voltage, low-current power sources to supply the energy needed to excite the gas mixture used as a lasing medium. These lasers can operate in both continuous and pulsed mode, and the wavelength of the laser beam is 10.6 μm. Fiber optic cable absorbs and is destroyed by this wavelength, so a rigid lens and mirror delivery system is used. Power outputs for gas lasers can be much higher than solid-state lasers, reaching 25 kW.

Fiber laser

In fiber lasers, the gain medium is the optical fiber itself. They are capable of power up to 50 kW and are increasingly being used for robotic industrial welding.

Structure of Laser Machine

Aperture

A small opening through which the electromagnetic radiation pass.

Electronic assembly

A number of electronic components (i.e., "circuit elements", "discrete components", integrated circuits, etc.) connected together to perform (a) specific function(s), replaceable as an entity and normally capable of being disassembled.

Excimer Lasers

Lasers which use the noble gas compounds for lasing. Excimer lasers generate laser light in ultraviolet to near-ultraviolet spectra, from 0.193 to 0.351 microns. Gas Laser A laser in which the active medium is gas. The gas can be composed of molecules (like CO2), Atoms (like He-Ne), or ions (like Ar+).

Laser Resonator or Laser Cavity

The optical mirrors, active medium and pumping system form the laser resonator, which is also called Laser Cavity. Laser cavities can be divided into Stable Cavities and Unstable Cavities according to whether they make the oscillating beam converge into the cavity or spread out from the cavity.

Q-Switching

A method to create laser pulses. It modulates the Q (Quality) of laser cavity to build population inversion first, then release the accumulated energy suddenly, in this way high energy pulses can be created.

Stable Cavity and Unstable Cavity

Cavities can be identified as stable or unstable according to whether they make the oscillating beam converge into the cavity or spread out of the cavity, if converge it is stable, if spread out, it is unstable.

Theory of Laser Machine

The laser generating theory is for YAG metal laser cutting machine. A HID xenon lamp is the excitation source and ND:YAG crystal is the working media. The radiation light of the HID xenon lamp focuses on ND: YAG crystal symmetrically and effectively to get the highest pumping efficiency. HID xenon lamp excites ND:YAG Crystal to generate the laser beam. The laser beam is vibrated and magnified in the resonant cavity which is between a total reflection lens and a half reflection lens to make the laser beam with high energy and density. Only qualified Laser beam can output through the half reflection lens to the beam expander. The laser diameter is increased and the energy angle is also decreased while laser shooting through the beam expander. Then the laser passes through 45º lens to change light path and focus lens make the beam focusing. The gas nozzle compresses gas and also makes the beam output concentrically.

Laser

Laser is the acronym of Light Amplification by Stimulated Emission of Radiation. Laser is light of special properties, light is electromagnetic (EM) wave in visible range. Lasers, broadly speaking, are devices that generate or amplify light, just as transistors generate and amplify electronic signals at audio, radio or microwave frequencies. Here light must be understand broadly, since lasers have covered radiation at wavelengths ranging from infrared range to ultraviolet and even soft x-ray range.

Stimulated absorption

When the atoms at lower energy levels absorb the incident energy with corresponding frequency, they jump to upper level states, this is called Stimulated Absorption.

Stimulated emission

Under the action of the incident electromagnetic field with the corresponding frequency, the atoms at upper level have a certain possibility to jump to the corresponding lower levels, emitting electromagnetic waves or photons with the same frequency, direction and phase with the incident waves. This process is called Stimulated Emission.

YAG
Yttrium/aluminum garnet.

Xenon lamp

A xenon arc lamp is a specialized type of gas discharge lamp, an electric light that produces light by passing electricity throughionized xenon gas at high pressure. It produces a bright white light that closely mimics natural sunlight. Xenon arc lamps are used inmovie projectors in theaters, in searchlights, and for specialized uses in industry and research to simulate sunlight. Xenon headlampsin automobiles actually use metal-halide lamps where xenon arc is only used during start-up.

Radiation

Radiation is a process in which energetic particles or energetic waves travel through a vacuum, or through matter-containing media that are not required for their propagation. Waves of a mass filled medium itself, such as water waves or sound waves, are usually not considered to be forms of "radiation" in this sense.

Beam expander

Beam expanders are optical devices that take a collimated beam of light and expand its size (or, used in reverse, reduce its size).

Lens

A lens is an optical device which transmits and refracts light, converging or diverging the beam.[citation needed] A simple lensconsists of a single optical element. A compound lens is an array of simple lenses (elements) with a common axis; the use of multiple elements allows more optical aberrations to be corrected than is possible with a single element. Lenses are typically made of glass or transparent plastic. Elements which refract electromagnetic radiation outside the visual spectrum are also called lenses: for instance, a microwave lens can be made from paraffin wax.

Beam diameter : Defined as the diameter of a circular beam at a certain point where the intensity drop to a fraction of its maximum value. The common definitions are 1/e (0.368) and 1/e2 (0.135) of the maximum value.


The zero-power resistance value(RT)

The zero-power resistance value R(T) is the resistance value measured at a given temperature T with the electrical load kept so small that there is no noticeable change in the resistance value if the load is further reduced.

Rated resistance (R25)

The rated resistance RR is the resistance value at temperature TR.PTC thermistor are classified according to this resistance value. The temperature TR is 25℃,unless otherwise specified.

Minimum resistance (Rmin)

The beginning of the temperature range with a positive temperature coefficient is specified by the temperature T(Rmin). The value of the PTC resistance at this temperature is designated as Rmin. This is the lowest zero power resistance value which the PTC thermistor is able to assume. 

Switch temperature (Tc)

In the resistance-temperature characteristic curve, the temperature value of PTC, when the resistance is 2 times of the minimum resistance value

In the resistance-temperature characteristic curve, the temperature value of PTC, when the resistance is 2 times of the minimum resistance value.

(Temperature coefficient:a)

a= dlnR/dT=(lnR2-lnR1)/(T2-T1) x100%/ ℃

V-I   characteristic

Response Time

The time  of current value  change from the  biggest  to half of the biggest.

NTC

See Negative temperature coefficient (NTC).

Positive temperature coefficient (PTC)

A PTC thermistor is one whose zero-power resistance increases with an increase in temperature.

PTC

See Positive temperature coefficient (PTC)

PTC thermistor for motor starting

Applied for motor starting in various home appliances like refrigerators and air-conditioners Applied for motor starting in various home appliances like refrigerators and air-conditioners.

Adding a PTC in the air conditioning compressor, the starting torque can be increased to overcome the resistance. Ensuring the equipment starting fastly and smoothly, and improving the ability of the device to adapt to the environment.

PTC thermistor for over-current and over-heat protection

A current limiting circuit is typically designed like that ,under normal circuit conditions ,the PTC internal temperature is just below its switch temperature .When excessive current begins to flow through the circuit ,the PTC quickly heated to beyond its switch temperature ,causing its resistance increase dramatically .This results in an immediate shut off the circuit .When the excessive current is removed ,the PTC resistance goes down and the c circuit returns to normal conditions. They not only respond to inadmissibly high current but also If a preset temperature limit is exceeded.

PTC thermistor as heating element

Applied in air-adjuster, wet wipe off, dryer, suit-dryer, moveable heater and low-voltage home appliances, automobiles etc that need warm air.

Principles:

PTC thermistor temperature fever with temperature characteristics The principle is that PTC thermistor increase access to electricity from thermal resistance jump warming, PTC thermistor temperature heat to maintain a constant surface temperature, The PTC thermistor temperature only with the Curie temperature and applied voltage, and the ambient temperature and unrelated.      PTC heating devices is the use of heat PTC thermistor temperature characteristics of the design of the heating temperature heating device. PTC thermistor temperature heating can be made into a variety of different shape and structure specifications, it is common to the disk, rectangular, long rectangular, Circle and other porous honeycomb. PTC heating elements above and metal structures can form various types of combination Power PTC heating devices.

Temperature sensor(used in automotive air conditioning, body and engine of automatives, chassis)

(1)evaporator temporature sensor: installed on the surface of evaporator, to perceive the temperature on the surface of evaporator, to avoid frosting on the surface of evaporator;
(2)air temperature sensor in/outside car: to perceive the the temperature in/outside automobile, installed on the front bumper,rearview mirror and instrument panel;
(3)engine coolant temperature sensor: to perceive the temperature of water tank, installed on the water tank of enginge;
(4)air temperature sensor in car: to test the tempera-ture at the position of car air-conditioning outlet;  
(5)other temperature sensors having integrated system application needs.

air temperature sensor in/outside car: to perceive the the temperature in/outside automobile, installed on the front bumper,rearview mirror and instrument panel;

1、nominal zero-power resistance and its permissible variation:
R25℃=2.200KΩ±3%             
R0℃=6.270KΩ±4%
2、material constant: B25/50=3500K±1%
3、insulation resistance(sensitive head):
≥100MΩ
4、thermal time constant:
τ≤60S(25℃ underwater~0℃ underwater)
5、operating temperature range:
-30℃~+85℃
6、storage temperature range:
-40℃~+90℃
engine coolant temperature sensor: to perceive the temperature of water tank, installed on the water tank of enginge;
1.nominal resistanceominal and its permissible variation:
R25℃=10kΩ±2%
2.operating temperature and resistance:
R-30℃=177kΩ±6%  
R+80℃=1.256kΩ±4%
3.thermal time constant:
τ≤10s(从50℃~25℃ underwater).
4.operating temperature range:
-30℃~+100℃
5.storage temperature range:
-40℃~+120℃
6.insulation resistance:
(500V.DC)≥100MΩ

air temperature sensor in car: to test the tempera-ture at the position of car air-conditioning outlet, and decide whether to heat;

1.nominal resistance and its permissible variation:
R25℃=100kΩ±2%
R100℃=6.8kΩ±4%
2.thermal time constant:
τ≤15s(从60℃~25℃ in the air
3.operating temperature range:
-30℃~+100℃
4.storage temperature range:    
40℃~+120℃
5.insulation resistance:  
(500V.DC)≥100MΩ

Light Sensor

Used in automotive air conditioning, body

Solar Light Sensor

It is used to perceive the intensity of infrared in the light, to decide whether the car air conditioning open automatically or not. It is used in automatically air conditioning system, and it has a differentiate between single zone and multizone;

Ambient Light Sensor

It is used to perceive the intensity of light, to decide whether the headlights of car open automatically or not( It belongs to active safety system. When the car drives through the tunnel quickly, and it becomes darker suddenly, the headlights will open automatically. Thus the accidents will reduce). It is used in automatically lighting system;

Integrated Light Sensor

(Solar and Ambient Light Integrated Sensor): Combining these two fuction togather will lower the price effectively.

Humidity Sensor

It is used in automatic demist system, belonging to active safety system. When the sensor detects that the glass is froging, it will prompt the automatic demist system open, to reduce the occurance of accidents.

Electronic Temperature Control:

Docking with evaporator temperature sensor, used in  turning on/off of compressor.

Speed-adjustment Resistance:

To ajust the volume of blower of AC system (mainly used for manual air conditioning system)

Product Feature

1. The error limit of  resistor resistance is ±10% 
2.There are no flaw on the surface of resistor. The construction is sound with  no loose
3.The products should meets the requirements of  QC/T413-2002 basic technical criteria of automative electronical equipment
4.The products should meets the requirements of  GB 18655-2002 Limits and method of measurement of radio disturbance characteristics for protecting vehicle-mounted receiver
5.The products should meets the requirements of GB/T17619-1998 Limits and method of measurement of electromagnetic radiation disturbance rejection of  automotive electronic components

Automative air conditioning damper actuators (servo motor)

To adjust the position of air conditioning damper (mainly used for automative and electronic air conditioning system)


Optical Glossary

2D3D Holograms Holographic images in which depth is indicated by a series of two dimensional planes are known as a 2D3D holograms. True 3D holographic images are of models or objects which, in themselves, occupy volume in space. The artwork for 2D/3D holograms is easy to produce because each layer is printed onto a two dimensional sheet. Stacking these sheets and making a hologram of the stack produces parallax effect which the eye perceives as image depth.

C

Casting. A method of embossing whereby a film of soft resin is applied to a nickel shim then exposed to ultraviolet light causing the resin to harden by cross linking. The resin film can now be removed and retains a faithful copy of the surface relief image that was present on the shim. This method of transferring an image from a nickel shim onto a plastic film, results in a bright image and causes very little wear to the shim.

Classic hologramA classic hologram is usually made using a 3D object, often a model. A laser beam is split in two and part is diverted onto the object, reflected off it then allowed to combine (or interfere) with the other part of the beam known as the reference beam. The classic hologram is a recording of the interference pattern. A well known example of such an image would be the small dove used by Visa on their credit cards.

D

Demetallisation: a two stage process in which metal, usually aluminium, is deposited onto the hologram and then selectively removed. The removal is achieved by either first printing a protective resin onto the metallic layer then dissolving away the unprotected metal, or ablating the metal with a laser beam.

Diffraction:a phenomenon whereby light waves are bent as a result of passing through small apertures whose dimensions are comparable to the wavelength of light. Of particular interest are gratings with line spacings close to the wavelength of light because these have the ability to bend light of different wavelengths by different amounts. Hence they produce a prismatic effect of splitting white light into the various colors of the rainbow.

Dot matrix: a surface relief hologram built up from an array of tiny diffractive gratings arranged at certain angles, is called a dot matrix hologram. The 'dots' are a point at which two microscopic beams of laser light meet at an angle and produce an interference pattern. In a dot matrix machine, a mechanical arrangement moves this point of light in a matrix pattern relative to a photosensitive plate. According to the final image required, the angle at which each dot is exposed into the matrix is determined by mathematical calculation. It is thus possible to construct fully synthetic images of objects that never existed in real life.

E

Embossing (hard & soft): embossing is the process whereby a surface relief hologram on a nickel shim is transferred to a relatively inexpensive plastic film. The shim or shims are mounted onto a cylinder and pressed into a thermoplastic film with heat and pressure. If the film is a tough plastic such as polyester, or is coated with a thin layer of metal to make it reflective, the process is called hard embossing and the lifetime of the embossing shim is relatively short. In such a process, the image may be exhausted from the shim after only a few hundred feet of embossing. For this reason, the plastic film is usually coated with a softer layer which deforms more easily under heat and pressure. This is called soft embossing and many thousands of feet can be produced before the embossing shims need to be replaced.

Eye-mark (or registration mark): where some step in the overall manufacturing process requires a machine to process a single holographic image, an eye mark (or registration mark) is invariably place next to each image. Examples of such processes are e.g where an automated die cutter must cut an individual image and convert it into a label. Another example might be where a roll of registered image holograms on a roll of hot stamping foil must have the discrete images stamped onto something. In each case, the cutting or stamping machine will advance the image until the next registration mark is optically detected and then the image is either cut or stamped. These marks are usually square in shape and consist of a diffraction grating allowing the mark to be detected at a specific angle.

G

Grating: a grating is a series of parallel lines having a spacing comparable with the wavelength of light. Such an array of lines has the ability to split white light into a rainbow because the different wavelengths are bent, or diffracted, by different amounts. Such gratings were originally produced by using a diamond to rule closely spaced lines onto glass but they are now more often produced by optical interference.

H

Hologram: the term 'hologram' is derived from two Greek words 'holos' meaning whole or complete and 'graphos'meaning an image. The term therefore describes a recorded image which is complete, in that it shows the whole volumetric space of the object or image, as opposed to a conventional picture, painting or photograph which displays an object from a single viewpoint. In a conventional two dimensional picture (2D) side to side movements of the viewer relative to the image do not supply any more information about the subject but if 'The Laughing Cavalier' had been a hologram, then such a movement would have enabled the viewer to see first one ear and then the other in the manner of viewing a statue.

Hot stamping foil (HSF): a thin material which is applied to paper or other substrate through the combination of heat and pressure. HSF can be used to support holographic images which can be transferred, using heat and pressure, onto another substrate such as paper or plastic. The layers containing the holographic image are extremely thin, typically 5-6 microns. Therefore they need to be supported on a thicker material such as 19 micron thick polyester. The action of stamping the foil with a heated die causes a 'release' layer between the hologram and the polyester support, to melt while simultaneously softening an adhesive 'size' coating. These combined effects allow the hologram to leave the polyester support and adhere, irreversibly, to its new location.

HRI, or High Refractive Index: in situations where a transparent hologram is required, e.g, for use as a laminate to cover the variable data of a passport or other ID document, instead of coating the holographic image with a metallic film, a transparent coating is made using a material with High Refractive Index. If transparency is achieved by simply not coating with metal, the image will disappear with handling or when an adhesive is applied because the microscopic rideges and grooves fill with the adhesive or body oils, so that there is no diffraction and no hologram. The HRI materials used in this process are oxides (eg titanium dioxide) or sulphides (eg zinc sulphide).

M

Multi-channel: a holographic image in which different, usually unrelated images appear at different viewing angles. The most usual, and easiest to make, is for the images to flip from one to another as the hologram is tilted from side to side. The most difficult is for the image to change as the hologram is rotated.

P

Parallax: the phenomenon in an image which allows depth to be judged from the movement of near image elements relative to more distant ones. Traditional embossed holograms only display parallax from side to side but the lack of vertical parallax is rarely noticed.

R

Rainbow: a rainbow is the visual result of splitting white light into its constituent colors according to wavelength. The order of the colors is red, orange, yellow, green, blue, indigo, violet with red having the longest wavelength and violet the shortest. The natural phenomenon is caused by the prismatic effect of raindrops in the sky but it can also be caused by diffractive gratings with a spatial frequency approaching the wavelength of light.

Recombination: the 'step and repeat' process whereby a single, holographic image is laid out in rows and columns in preparation for shim production. It can either be carried out mechanically or optically. In the mechanical process, the single image is made into a stamper which is impressed at pre-determined intervals, into a plastic sheet. If done optically, the single image is exposed in a predetermined pattern onto a (glass) plate coated with a photoresist.

Reflection hologram: see volume hologram. These are viewed by the reflection of white light. The diffractive planes within the depth of the recording material have a spacing which corresponds only to a single wavelength of light. This wavelength, usually green or yellow, is reflected back and reconstructs the image, the other colors being transmitted and absorbed by a black backing placed behind the hologram.

S

Shim: a 'shim' is a thin plate of metal, usually nickel, which is attached to a cylinder in preparation for the embossing process. The shim is produced by an electro-deposition process whereby the plate with the recombined images is immersed into a galvanic tank and metallic nickel is caused to accumulate on its surface. This metal plate is usually referred to as the 'master' or 'mother' shim. It is usually used to prepare 'daughter' shims which are used for the mechanical embossing process.

Shim line: at some point in the hologram replication process, one or more metal shims need to be mounted around the circumference of a metal cylinder (the embossing cylinder). The point at which the shims join often produces a visible line in the resulting embossed film. This line is most objectionable where the finished result is intended to be a continuous pattern. Those skilled in the art have developed procedures which successfully minimise or even eliminate such optical discontinuities in the final product.

Stereogram: this is a hologram prepared using the sequential images from a piece of movie footage. Each frame of the movie is converted into a vertical slit image and stacked against another slit image of the adjacent frame. The result is a hologram which, when the viewing angle changes side to side (usually), the same image motion as the movie footage is seen as the frames are seen one after another. The technique usually employs around 100 movie frames equivalent to only a few seconds of action.

Surface-relief hologram: a surface relief hologram is one in which all the details of the image are recorded as an interference pattern on the surface of some material. It can be imagined as the ripples on water frozen in time except that the ripples are the interference patterns arising when two laser light beams interfere with each other, and the ripples are tiny, with a frequency close to the wavelength of light. The value of such surface relief holograms is that they can be mass replicated by mechanical transfer from a master image to inexpensive plastic.