CN109516697A

CN109516697A - The laser polishing method of mobile phone display screen glass

Info

Publication number: CN109516697A
Application number: CN201910026992.8A
Authority: CN
Inventors: 邵建达; 贺婷; 魏朝阳; 蒋志刚; 路晴
Original assignee: Shanghai Institute of Optics and Fine Mechanics of CAS
Current assignee: Shanghai Institute of Optics and Fine Mechanics of CAS
Priority date: 2019-01-11
Filing date: 2019-01-11
Publication date: 2019-03-26

Abstract

The present invention is a kind of laser polishing method of mobile phone display screen glass, this method uses laser polishing mobile phone display screen glass, utilize beam shaping optimization order laser light source, preheating step solves the problems, such as that mobile phone display screen glass heat effect is frangible, and realization carries out contactless lossless high quality to mobile phone display screen glass and efficiently polishes.The present invention provides a kind of new method efficiently, economic to obtain the processing of lossless smooth mobile phone display screen glass.

Description

The laser polishing method of mobile phone display screen glass

Technical field

The present invention relates to the polishing of mobile phone display screen glass, especially a kind of laser polishing method of mobile phone display screen glass

Background technique

Numerous characteristics such as resolution ratio, light transmittance etc. are all related with glass substrate in mobile phone display screen, and glass substrate is hand Important component in machine display screen.The fast development of Smartphone device has a large amount of demand to mobile phone display screen glass, such as every Two panels glass substrate is needed in piece LED display, needs a piece of glass substrate in OLED display screen, 2015, annual production 2.57 OLED, it is predicted that the year output of the year two thousand twenty OLED will be up to 700,000,000.Mobile phone display screen glass density is lower, springform Measuring larger, small thermal coefficient is typical difficult to machine material.Currently used mobile phone display screen glass processing polishing technology is to change Mechanical polishing is learned, reacting to be ground by abrasive grain again with workpiece surface using the chemical substance in polishing fluid generates film, and It constantly repeats, until surface quality meet demand.Though cmp method can obtain the glass substrate met the requirements, its There are still many problems, and as polished glass surface exists, machinery is scratched and supplied materials sags and crests, yield are difficult to improve；Polishing fluid at This height, utilization rate consumption is big, and polishing fluid will cause pollution to environment；Polishing time-consuming is at low efficiency etc..

Laser polishing is a kind of novel polishing technology, and laser polishing mobile phone display screen glass is based on CO₂Laser melting The Physical Mechanism of polishing is a kind of contactless polishing method.This method uses continuous CO₂Laser beam high-velocity scanning glass substrate Surface, control surface temperature are higher than softening temperature and are lower than gasification temperature, viscosity of material decline, mainly in the effect of surface tension Smooth surface, removal of the whole process without material.Contactless polishing mode, but not to surface does not cause to damage, simultaneously Can also the scratch on smooth starting element surface, defect, realize the not damaged smooth, polished of high-precision.Laser polishing, which also has, to be polished to The advantages that this is low, is not necessarily to polishing fluid, and safety non-pollution is easily manipulated, flexibility height, and polishing efficiency is high.Mobile phone display screen glass For thin sheet glass, Laser beam energy distribution is more evenly more advantageous to the polishing to mobile phone display screen glass, compared to Gaussian Profile Laser beam, flat top beam distribution have the characteristics that light beam is flat, Energy distribution is uniform.The thermal expansion of mobile phone display screen glass material Coefficient is larger, CO₂Laser, which directly acts on, will lead to glass fragmentation faced, and preheat showing using mobile phone when can reduce polishing for platform The temperature gradient of panel glass, preheating can prevent mobile phone display screen glass chipping existing due to heat effect in polishing process As, while preheating can reduce thermal stress to a certain degree.

Summary of the invention

The present invention provides a kind of laser polishing method of mobile phone display screen glass, utilizes CO₂Laser polishing mobile phone display screen Glass, and laser beam shaping, preheating, temperature real time monitoring and feedback are combined, realize the efficient hand of lossless high quality Machine display screen glass laser polishing new method.

The technology of the present invention solution is as follows:

A kind of laser polishing method of mobile phone display screen glass, comprising the following steps:

1) polishing light source setting: CO is selected₂Laser light source, and be flat-top by Gauss beam reshaping using beam shaping system Light beam；

2) clean polished mobile phone display screen glass mobile phone display screen preheating glass: is placed on a thermally equivalent It is preheated on preheating platform, preheating temperature is arranged by polishing demand in preheating platform；

3) polishing path planning and other parameters setting: according to experiment demand select polishing path, scanning speed according to Laser optics energy, spot size and institute's polishing material are set as 1m/s to 10m/s etc., sweep span setting less than four/ One laser diameter (1/e²)；

4) real time temperature detection and feedback: polishing optical element temperature using pyrometer or thermal infrared imager real-time monitoring, When polished regional temperature is higher than material gasification temperature or preset temperature, light source laser energy is reduced；When polished region When temperature is lower than preset temperature, the laser energy of light source is improved, keeps polishing cell phone screen glass process temperature uniform；

5) cooling down: after laser polishing mobile phone screen be placed on preheating platform on preheating platform gradually cool down it is cold But, or it is moved to clean holding furnace furnace cooling, misoperation is avoided to cause cell phone screen glass fragmentation；

Select continuous or pulse CO₂Laser, and the light beam being composed using non-spherical lens group and spatial filter Gauss beam reshaping is that light beam is flat, the uniform flat top beam of Energy distribution by orthopedic systems；

The preheating temperature of preheating platform is arranged according to material property, approaches and be lower than the strain temperature of material, it is ensured that polishing Process mobile phone display screen glass will not fragmentation not will cause thermal distoftion simultaneously；

Scan path includes S type scan path, the round-trip scan path of single effect, pseudo random scanning path or other scannings Path.

The polishing mode of mobile phone display screen glass of the invention is a kind of contactless polishing using laser polishing Method will not cause scratch equivalent damage compared with other current polishing methods to surface, greatly improve the yield of polishing step, There is better surface roughness.CO₂Equipment price needed for the method for laser polishing is more compared to traditional numeric-control polishing method cost It is low；The mode of laser beam polishing may be up to m/s using the quick scanning cell phone screen glass speed of laser, polish a piece of sample when Between than traditional polishing mode can shorten several times even tens times, be greatly improved polishing efficiency and shorten the production cycle.

Specific embodiment

Below with reference to example, the present invention is described further.

Embodiment 1

1) polishing light source setting: continuous CO is selected₂Laser light source, and be by Gauss beam reshaping using beam shaping system Light beam is flat, the uniform flat top beam of Energy distribution；

2) clean polished mobile phone display screen glass mobile phone display screen preheating glass: is placed on a thermally equivalent It is preheated on preheating platform, the cell phone screen glass of polishing are Corning Gorrilla glass, and the strain point of the glass is 571 DEG C, annealing temperature is 623 DEG C, and preheating platform is 500 DEG C by polishing demand setting preheating temperature；

3) polishing path planning and other parameters are set: the cell phone screen glass of polishing are that plane selection single effect is past The polishing path for returning scanning, according to CO used₂Energy of lasers is 100W, position spot diameter is 3mm and setting polishing Speed is 275mm/s, and sweep span is set as 50 μm；

4) real time temperature detection and feedback: using pyrometer monitoring polishing optical element temperature, when polished regional temperature When higher than material gasification temperature or preset temperature, light source laser energy is reduced；When polished regional temperature is lower than presetting temperature When spending, the laser energy of light source is improved, keeps polishing cell phone screen glass process temperature uniform；

5) cooling down: after laser polishing mobile phone screen be placed on preheating platform on preheating platform gradually cool down it is cold But；

After tested, above-mentioned laser polishing mobile phone display screen glass, initial roughness RMS are reduced to by 424.991nm 36.089nm, and cell phone screen glass no marking after laser polishing, roughness measurement equipment are white light interferometer (NewView 7300), 1 × 1mm of detection range²。

The burnishing parameters of embodiment 2 to embodiment 10 are as shown in table 1.

Embodiment 2~10 mainly investigates the mobile phone display screen glass of different initial roughness Corning Gorrilla materials In laser polishing process, scanning speed, scanning mode, preheating temperature swash the influence on surface to mobile phone display screen glass.Specifically With embodiment 1, difference is to change scanning speed, scanning mode and preheating temperature implementation process.It is obtained, is tested by experimental result Using 100W, spot diameter 3mm laser, optimal burnishing parameters are as follows: 500 DEG C of preheating, the round-trip scanning mode of single effect is swept Retouch spacing 0.05mm, mobile phone screen that initial roughness RMS is 424.991nm show glass when scanning speed is 275mm/s, The mobile phone screen that surface roughness RMS to 36.089nm, initial roughness RMS are 270.279nm shows glass in scanning speed When for 325mm/s, surface roughness RMS to 25.185nm, and laser polishing rear surface almost no marking.

Table 1 is the polishing condition of the embodiment of the present invention:

Claims

1. a laser polishing method of mobile phone display glass, it is characterized in that this polishing method comprises the following steps:

1) Polishing light source setting: choose CO ₂ laser light source, and use the beam shaping system to shape the Gaussian beam into a flat-top beam;

2) Mobile phone display glass preheating: place the clean mobile phone display glass to be polished on a uniformly heated preheating platform, and the preheating platform sets the preheating temperature according to the polishing requirements;

3) Polishing path planning and setting of other parameters: select the polishing path according to the experimental requirements. quarter laser diameter (1/e ² );

4) Real-time temperature detection and feedback: use a pyrometer or an infrared thermal imager to monitor the temperature of the polished optical components in real time. When the temperature of the area to be polished is higher than the vaporization temperature of the material or the preset temperature, reduce the laser energy of the light source; When the temperature is lower than the preset temperature, the laser energy of the light source is increased to make the temperature uniform in the process of polishing the glass of the mobile phone screen;

5) Cooling and cooling: After the laser polishing is completed, the mobile phone screen is placed on the preheating platform and gradually cooled and cooled, or moved to a clean holding furnace to cool with the furnace.

2. the laser polishing method of mobile phone display glass according to claim 1 is characterized in that selecting continuous or pulsed _CO laser for use, and utilizing the beam shaping system or other beam shaping that aspheric lens group and spatial filter are combined to form system to shape the Gaussian beam into a flat top beam with a flat beam and a uniform energy distribution;

3. The laser polishing method of mobile phone display glass according to claim 1 is characterized in that the preheating temperature of the preheating platform is set according to material properties, and is close to and lower than the strain temperature of the material, so as to ensure that the mobile phone display glass is not polished during the polishing process. will shatter without causing thermal distortion.

4 . The laser polishing method for mobile phone display glass according to claim 1 , wherein the scanning path comprises an S-shaped scanning path, a one-way action round-trip scanning path, a pseudo-random scanning path or other scanning paths. 5 .