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Small pixel led display is not harmful to eyesight.

Small pixel led displays are welcome in a number of occasions by people of all ages because of its unique high brightness, wide color gamut, high contrast and other advantages, however, the small pixel led display light to human eye bio-security issues have also to be taken into attention. HSTV find an evidence to tell the small pixel led display is not harmful to eyesight, see as below:

Chinese Institute of Metrology took accordance with the existing international standards, measured the bio-security of a p1.67 led display from both the blue light hazards to retina and the thermal hazards, and took comparison with a plasma TV and a LCD TV.

Test results show that, at the same brightness and white field conditions, although the peak brightness of the led display is higher than the other two samples in blue band, but its narrow band characteristics resulting weighted scored retinal hazard index not higher than plasma TV and LCD TV. The retina bio-security measured data has no significant differences between the three displays, the led display measurement results even better than the other two displays.

Whats should be keep in mind is that any display can cause permanent eye damage if keeping long-term view on the screen, thus, no matter what form of display is used, the audiences should pay attention to eye health and maintain good habits with the eyes. Work and rest combined is the best way to protect their eyesight.

How to deal with led display screen failure?

There are various reasons for full color led display screen failures, HSTV made a summary for how to how deal with such failures, see as below:

If the new display gets breakdown when powered on, maybe it’s because the scan mode on control card setting is wrong or the flat cable is plugged wrongly (check the connect between sending card and the first PCB board), and the 5v power supplier improper connection will also cause the issue.

If the display suddenly gets breakdown after it is used for a while, except the failure on control card, the most probably reason is the chips or power supplier gets short circuit burned due to water leakage.

The possible reasons for display failure can also be graphics card failure or driving problems. The user can check if the DVI output signal of the graphics card is normal by connecting the DVI interface on a display, usually the resolution for LINSN control card DVI interface is 1024×768 dots. Then remove the LAN cable on the sending card behind the display and press the debug button on the receiving card to check if the display scan mode is normal or not.

1. Led display no response.
Solution: check if there is 220V electricity input to the led display.

2. Led display doesn’t work properly.
Solutions:
(1) Check if the control card parameters settings are correct and whether signals are sent to the control card.
(2) Check whether the communication line is working normally and if signals are sent to the control card.

(3) Check if the control card is well connected with the 5V power supplier.

3. Parts of the led display screen don’t work properly, such as black screen and breakdown.
Solutions: Check if the power supplier for the abnormal part is working properly; check the connection of the signal cable for the part; check the single led module malfunction.

Output problems:
1. Check the whether the line connections between the output interface and signal output IC is short circuit or not.
2. Check the output clock latch signal is normal or not.
3. Check if the concatenation data output mouth and the output interface mouth between the last drive IC are short circuit.

4. Poor heat emission in computer results in high temperature on graphics card and causes led display failure.
Solutions: solve the heat dissipation problems. Check if the fans are working properly and refuel the fans, clean the dust inside the case. After solving the heat dissipation problem, led display will work normally.

5. LED display failure due to reinstall the system and the computer graphics card or the display doesn’t match the high resolution on led display.
Solutions:
(1) Restart the computer, continuous press F8 key, choose to enter the “safe mode” in the advanced boot menu and press enter key to login the system. Then enter the display settings under Windows mode, select 16 colors, click “apply” button, click “ok” button.
(2) Restart the computer, enter the device manager in the Windows normal mode, remove the graphics card drivers and restart the computer again.

All above mentioned are the reasons for full color led display failures and the corresponding solutions. They are provided by optokingdom, optokingdom is an online shopping mall built by Haisheng led Co., Ltd aimed at providing led display and relative accessory products and services.

How to remove the moire effect on led display screen?

Clients always doubt our led display quality because they always encounter with the moire and scan lines when they use their phones and cameras to take photos of our led display. In fact, the phenomenon is not caused by the display itself but caused by the shooting angle and camera focal length. What is the moire? HSTV gives the answer as below:

The moire is not the scan lines. There are several differences between them:
1. Usually the moire is in inconstant arc diffusion state but the scan lines are horizontal black stripes straight lines.
2. The moire is a manifestation of the the beat principle but the scan lines are caused by the low display refresh rate which are caught by the camera.

The process of generating moire:
1. Two strips which have slight difference in spatial frequency have the same black line position on the left end, because of the same interval 丌, they will be coincident gradually on the right side.
2. The moire is the result of the strips coincide: the white lines are obvious but because of the coincidence of the white and black lines on the right side, the overlapping results become all black. All the black and white lines coincidence results the composition of the moire.

The way to remove moire
1. Change the camera shooting angle, slightly changing of the camera shooting angle can remove or reduce the moire.
2. Change the camera shooting position to reduce the moires.
3. Change the camera focus to change the resolution so as to remove the moires.
4. Change the camera camera focal length to remove or reduce the moires.
5. Insert mirror filter in front of the CCD to reduce the moires.
6. Use software such as the Photoshop to remove the moires on the final images.

How to deal with the led display tail cargo chromatic aberration?

It’s unavoidable to keep tail cargo during LED display sales, because the tail cargo are for different batches of products they are unavoidable to have chromatic aberration and this can result in poor display effect when they are splicing into one display. In this situation HSTV suggests to do spot-spot calibration for the display.

The entidifferenzierung spot-spot calibration technology is used to upgrade the led display brightness luminance uniformity and color fidelity. By collecting data for each pixel on the screen, it can make a correction coefficient matrix and feedback to the display control system, then the control system can make difference driven for the pixels so as to reduce the brightness and color differences for the pixels. This technology can make the display which is made of different tail cargo displays pure and fine and natural images.

1. According to its applications, the spot-spot calibration technology can be divided into two fields:

A:  spot-spot calibration for single led cabinet during production, all the cabinets will be with high uniformity before delivery.

B:  the led display is calibrated on scene to get good uniformity and display effect for a certain on site observation distance.

2. Spot-spot calibration can be divided in to colorimetric calibration and brightness calibration :

A:  brightness calibration is for the LED illumination intensity, because some of the calibration devices are lack of good color acuity, they can’t measure the accurate differences of spectral, thus they are used for measuring LED illumination intensity instead of measuring accurate chromaticity distortion.

B:  colorimetric calibration is to measure accurate LED brightness and colorimetric values by using photometer equipment that have good color acuity.

The tail cargo led display is cheaper than normal products in market but because of the spot-spot calibration technology the display can perform normal functions, because it is calibrated to keep good screen brightness consistency.

How to choose suitable LED power supply for led display?

led Power supply is playing an important role to the quality of a led display, but how to choose suitable power supply for led display? The answer is on www.optokingdom.com.

Three points for selecting power supply:

1. Application environment conditions: temperature, humidity, sand and dust, installation method.

2. Electrical application condition: lightning protection, PF value, loading voltage, safety grounding wire.

3. Laws and industry regulations: certifications requirements, environment requirements, EMC requirements.

Six points for checking the power supply quality:

1. Environment: power supply should have wide working temperature range, good humidity performance and high protection level and so on.

2. Input voltage: to make sure normal output, the power supply should have wide input voltage so that it can be used well in both high voltage condition and low voltage condition.

3. Power factor and conversion efficiency: the higher power factor the better for power supply because higher power factor is good for improve the utilization rate of power grid, so as the conversion efficiency does because it can improve the effective power utilization rate and reduce the subsequent cost.

4. Voltage stable accuracy: power supply should have good voltage characteristic to ensure no voltage fluctuation when it is under light load and heavy load conditions.

5. Material grade: select international real-name brand components can prolong the service life of the power supply.

6. Certification requirements: due to the third party supervision, the materials for certificated power are restricted by the certifications, it has more reliable quality.

Safety precautions for led display cleaning job

Since the cleaning job is very necessary and important to make the led display keeping good performance in long term, what’s the safety precautions for led display cleaning job? HSTV gives suggestions as below:

There are two aspects to pay attention when doing cleaning job for led display:

1.  Pull out the power cord before cleaning.

2.  Select suitable cleaning liquid. The cleaning liquid generally includes electrolytem, high-purity distilled water, anti-static fluid etc. Choose the suitable qualified cleaning liquid can effectively remove the dust and other dirty mark on the display screen.

There are three steps for cleaning the led display:

1. First of all vacuuming: remove the dirt and dust from the surface of the screen mask.

2. Second wet cleaning: please note that the cleaning liquid can not be sprayed directly on the screen but should a little amount of the cleaning liquid should be sprayed on the cleaning cloth then gently wipe the screen along a same direction. You can also use the soft brush of a vacuum cleaner to brush the led lamps mask and remove the dirt.

3. Third drying: use vacuum cleaner suck the liquid which is left from the wet cleaning step, and make sure the display is clean and free of dust on the screen masks.

Different led display installation Summary

Generally speaking, the led display installation structures can be divided into floor standing type, building face side wall mounting type and roof top fixing type, each type has different stress and strain characteristics.

By comparing the finite element analysis of three kinds of supporting structure system, HSTV gets the corresponding optimization scheme for each supporting structure: the cantilever mast for floor standing structure should use circular cross section; the wall mounting type structure should use composite truss; the roof top fixing type structure should use space truss design. By making optimal design against the key joints on the supporting structure and making shear key or cross-shaped stiffening rib construction measures to optimize the node stress state, it can improve the safety performance of the supporting structures.

Floor standing supporting structure:

Floor standing led displays are usually installed in city squares or important traffic cross roads, HSTV suggests to use space steel truss structure. The foundation structure is made of 2 pieces of space lattice columns which are composed by 4 pieces of steel columns, and upper part which is for installing display will use multilevel horizontal space truss structure, in this way the structure can meet both the requirements of structure stress and the requirements for maintenance space preset.

Wall mounted led display installation structure:

There are limited space for floor standing installed led displays in cities because of the dense constructions, in order to make full use of led display dynamic image ads display functions in city commercial areas, the led displays are usually mounted on the building face side.

According to the building face side condition and  convertible condition as well as the display installation height above ground, the led display installation structures are divided into wall mounted structure and roof installation structure.

Wall mounted installation structures usually adapt a steel structure fastening on the building face side and the led display is fixed on the structure, between the display back side and the building face side there is a maintenance space for the display.

Roof installation structure

Because the wall mounted led displays cover large area of the building face side, it can affect the indoor lighting, thus wall mounted led displays are usually used for shopping mall and other large commercial building. The moderate height office building and residential constructions will install the led display on roof.

three designs for stage led display applications

IM-10-5

Along with the LED technology development, LED displays are widely used in stage applications. According to HSTV summary, there are three designs for stage led display applications.

First one: led display is designed as the whole background and side curtain for the stage, so that the display will do all the space-time changing, actors perform without real props.

The advantage of this design is to save money for the stage because a video on the screen can tell the whole story, but it has its defect that the stage lose its spatial characteristics, audiences will see flats on the stage at improper angles.

Second one: the led displays are the main parts of the stage but there are enough spaces for stage lighting devices around each display unit.

The led screens are hung orderly under stage truss framework, and between the screens there are Moving Head lighting equipment. The screens can enhance the stage screen depth and perspective effect, and the lighting equipment can increase the nice dynamic atmosphere. It’s defect is the stage structure is relatively simple and not vivid.

Third one: the large led display is the center of the stage or do as the stage backdrop, coupled with the real front to complete the stage sets.

This design makes the stage has strong sense of form and three-dimensional feeling, and there are enough space for stage lighting. Such a stage is consistent with the traditional aesthetic concepts, but also increases the elements of modern technology. Both the close shot and vista are real enough to give perfect stage display effect.

Of course there are various stage styles, and each time age also has its own form of stage performance, but led display has undoubtedly became the trend of this time, it can be seen every corner of our life and is indispensable on the stages. Science and technology are not the only means to create ideal stage effects, but our thought is the key for the stage innovation.

How to remove the moire effect on led display screen?

Clients always doubt our led display quality because they always encounter with the moire and scan lines when they use their phones and cameras to take photos of our led display. In fact, the phenomenon is not caused by the display itself but caused by the shooting angle and camera focal length. What is the moire? HSTV gives the answer as below.

The moire is not the scan lines. There are several differences between them:

1. Usually the moire is in inconstant arc diffusion state but the scan lines are horizontal black stripes straight lines.

2. The moire is a manifestation of the the beat principle but the scan lines are caused by the low display refresh rate which are caught by the camera.

The process of generating moire:

1. Two strips which have slight difference in spatial frequency have the same black line position on the left end, because of the same interval 丌, they will be coincident gradually on the right side.

2. The moire is the result of the strips coincide: the white lines are obvious but because of the coincidence of the white and black lines on the right side, the overlapping results become all black. All the black and white lines coincidence results the composition of the moire.

The way to remove moire

1. Change the camera shooting angle, slightly changing of the camera shooting angle can remove or reduce the moire.

2. Change the camera shooting position to reduce the moires.

3. Change the camera focus to change the resolution so as to remove the moires.

4. Change the camera camera focal length to remove or reduce the moires.

5. Insert mirror filter in front of the CCD to reduce the moires.

6. Use software such as the Photoshop to remove the moires on the final images.

how to make the led display keep good performance in long term?

During the usage of led display, the pollution, loose fasten, vibration, heat emission, temperature change and other reasons can cause a variety of failures to led display and result in  serious accidents, therefore, regular maintenance to led display is essential. So how to overhaul led display with clean up? HSTV gives suggestions as below:

Routing inspection:

General led display inspection is based on the monthly patrol and for large screen led display it’s better to do weekly routing inspection, the detailed requirements are as below:

1. Led display maintenance contents include inspection for led lamps, led modules, power supplier and control cards.

2. Led display control system maintenance contents include inspection for controllers, fiber optic converter card, distributor and sending card.

3. Led display programming system maintenance contents include the upgrade and maintenance to programs editing software.

4. Make regular (better monthly intervals) on-site inspection and maintenance to the system by technical staff.

5. Escort the major events: the company technical staff have to do on-site guidance to make sure activities are held smoothly.

Clean up:

For low protection level led display especially for outdoor led display, the atmospheric dust can get into the device through air vents, this can accelerate wear and damage to fans, and reduce the heat and insulating properties to the internal control device and even cause a short circuit when  the dirt absorb moisture in the air. And in long term the dust can cause mildew to PCB board and electronic components so as to reduce the display performance and error will occur. Therefore, led display cleanup job is simple but it’s a very important aspect to make the display keep good performance in long term.