1. LCD panel
The liquid crystal includes active liquid crystal and inactive liquid crystal. Inactive liquid crystals reflect light and are generally used in notebook computers and film projectors. The active liquid crystal has light transmission, and is made into an LCD liquid crystal panel, which is used in a projector. Through the control system, the brightness, color, contrast, etc. of the light passing through the LCD can be controlled.
The size of the LCD panel determines the size of the projector. The smaller the LCD, the smaller the projector's optical system can be made, thereby making the projector smaller. But to achieve high resolution and maintain high brightness on a very small LCD, the technical difficulty is conceivable. At present, most projectors used in conference rooms are 1.32-inch LCD liquid crystal panels, and portable projectors are 0.9-inch LCD liquid crystal panels. In 2000, there will be 0.7-inch LCD panels with physical resolutions of SVGA and XGA.
When evaluating a liquid crystal projector, in addition to the size of the LCD panel, it also depends on the number of LCD panels used by the projector. There are projectors with a single LCD panel and three LCD panels on the market. If there are many LCD panels, the number of pixels is large. Pixels are the basic units that make up an image. The larger the number of pixels, the finer the image.
Number of pixels = physical resolution x number of LCD panels
For example: SVGA model Number of pixels = (800x600) x3
2. Output resolution
Refers to the resolution of the image projected by the projector. Or called physical resolution, actual resolution, that is, the resolution of the LCD liquid crystal panel. The liquid crystal body is divided on the LCD liquid crystal panel by a grid, and one liquid crystal body is a pixel point. Then, when the output resolution is 800 x 600, it means that 800 pixels are divided in the horizontal direction of the LCD panel and 600 pixels are divided in the vertical direction.
The higher the physical resolution, the greater the range of receivable resolution, and the wider the adaptability of the projector. Physical resolution is often used to evaluate the value of LCD projectors.
3. Maximum input resolution
It means that the projector can receive a resolution greater than the physical resolution and project the signal through a compression algorithm.
1) The early projectors all used line extraction algorithm, namely: linear compression technology.
This algorithm has a disconnection problem.
2) The products of various manufacturers have launched new algorithms for compressing signals.
4. Horizontal scan line
Also called video scan line. Mainly used to evaluate the quality of video signals. The default refers to the NTSC system. Generally, VCD is 220 lines, LD is 450 lines, and DVD is 500 lines. The maximum number of lines supported by the projector is 700 lines.
5. Brightness
The International Standard Unit is ANSI Lumens. The measurement environment is as follows:
1) Distance between projector and screen: 2.4 meters
2) The screen is 60 inches
3) Measure the brightness of 9 points of the projection screen with a light meter pen
4) Find the average of the brightness of 9 points, which is ANSI lumens.
The projectors of various brands have different measurement environments. Although the ANSI lumens are the same, the actual brightness is different.
6. Color
Now, almost all projectors support 24-bit true color. So to evaluate the color reproduction of the projector, not only look at the color, but also look at the contrast.
7. Contrast
It is the ratio of black to white, that is, the gradation from black to white. The larger the ratio, the more the gradation from black to white, so the richer the color expression.
8. Picture size
Refers to the size of the projected screen. To put the required size, the projector needs to be placed at a distance corresponding to the screen.
According to different models, the relationship between the screen size and the projection distance is different.
9. Projection distance
Refers to the distance between the projector lens and the screen.
10. Uniformity
Refers to the ratio of the middle brightness of the cast screen to the surrounding brightness. The middle is generally defined as 100%.
11. Lens
F is the transmittance of the lens. The smaller F, the better the lens' light transmission.
Is the magnification ratio of the lens. 77/55 = 1.4, that is to say, at a fixed position, the picture can be enlarged 1.4 times.
12. Ceiling function
Hang the projector upside down to project on the roof. As shown below:
13. Rear projection function
Place the projector behind the rear screen for projection. As shown below:
14. Keystone correction
Some projectors can provide an electronic keystone correction function, which can easily correct the trapezoidal distortion of the screen caused by overhead shooting or ceiling projection.
15. Horizontal scanning frequency
Also called line frequency. The horizontal scanning frequency of the projector has a range. If the horizontal scanning frequency of the input signal from the computer exceeds this range, the projector cannot be turned on (NO SIGNAL).
16. Vertical scanning frequency
Also called Zhenpin. If the vertical scanning frequency of the input signal from the computer is outside this range, the projector will not be able to operate (NO SIGNAL). Within the range, when the computer's vertical scanning frequency is set to a high value, the projection effect is good.
17. Computer input interface
Refers to the input interface of the computer display signal. The conference room model generally has two interfaces, which can be connected to two computers at the same time, and the portable model generally only has one interface.
18. Computer output interface
Refers to the output interface of the computer display signal. The monitor can be connected via this interface. If the projector does not have this interface, you can use a VGA splitter to connect the monitor.
19. Video signal
For video signals can support three standards: NTSC, PAL, SECAM
20. Standard video input
With standard video input interface (RCA). Standard video signals are encoded when output, compressed and output, and decoded when received. This will lose some signals.
21. S video input
With S video input interface (S Video). Since the S video signal does not need to be encoded and decoded, there is no signal loss, so the S video signal is of better quality than the standard video signal.
22. Audio input and output
With audio input and output interface. You can input audio signals from computers, video recorders, etc. and play them through the built-in speakers. You can also connect the power amplifier and external speakers through the audio output interface.
23. Power supply
The lower the power of the power supply, the less heat the machine generates, so that the continuous projection time of the machine is longer. In order to use safety, the projector is usually equipped with overheat protection device.
The liquid crystal includes active liquid crystal and inactive liquid crystal. Inactive liquid crystals reflect light and are generally used in notebook computers and film projectors. The active liquid crystal has light transmission, and is made into an LCD liquid crystal panel, which is used in a projector. Through the control system, the brightness, color, contrast, etc. of the light passing through the LCD can be controlled.
The size of the LCD panel determines the size of the projector. The smaller the LCD, the smaller the projector's optical system can be made, thereby making the projector smaller. But to achieve high resolution and maintain high brightness on a very small LCD, the technical difficulty is conceivable. At present, most projectors used in conference rooms are 1.32-inch LCD liquid crystal panels, and portable projectors are 0.9-inch LCD liquid crystal panels. In 2000, there will be 0.7-inch LCD panels with physical resolutions of SVGA and XGA.
When evaluating a liquid crystal projector, in addition to the size of the LCD panel, it also depends on the number of LCD panels used by the projector. There are projectors with a single LCD panel and three LCD panels on the market. If there are many LCD panels, the number of pixels is large. Pixels are the basic units that make up an image. The larger the number of pixels, the finer the image.
Number of pixels = physical resolution x number of LCD panels
For example: SVGA model Number of pixels = (800x600) x3
2. Output resolution
Refers to the resolution of the image projected by the projector. Or called physical resolution, actual resolution, that is, the resolution of the LCD liquid crystal panel. The liquid crystal body is divided on the LCD liquid crystal panel by a grid, and one liquid crystal body is a pixel point. Then, when the output resolution is 800 x 600, it means that 800 pixels are divided in the horizontal direction of the LCD panel and 600 pixels are divided in the vertical direction.
The higher the physical resolution, the greater the range of receivable resolution, and the wider the adaptability of the projector. Physical resolution is often used to evaluate the value of LCD projectors.
3. Maximum input resolution
It means that the projector can receive a resolution greater than the physical resolution and project the signal through a compression algorithm.
1) The early projectors all used line extraction algorithm, namely: linear compression technology.
This algorithm has a disconnection problem.
2) The products of various manufacturers have launched new algorithms for compressing signals.
4. Horizontal scan line
Also called video scan line. Mainly used to evaluate the quality of video signals. The default refers to the NTSC system. Generally, VCD is 220 lines, LD is 450 lines, and DVD is 500 lines. The maximum number of lines supported by the projector is 700 lines.
5. Brightness
The International Standard Unit is ANSI Lumens. The measurement environment is as follows:
1) Distance between projector and screen: 2.4 meters
2) The screen is 60 inches
3) Measure the brightness of 9 points of the projection screen with a light meter pen
4) Find the average of the brightness of 9 points, which is ANSI lumens.
The projectors of various brands have different measurement environments. Although the ANSI lumens are the same, the actual brightness is different.
6. Color
Now, almost all projectors support 24-bit true color. So to evaluate the color reproduction of the projector, not only look at the color, but also look at the contrast.
7. Contrast
It is the ratio of black to white, that is, the gradation from black to white. The larger the ratio, the more the gradation from black to white, so the richer the color expression.
8. Picture size
Refers to the size of the projected screen. To put the required size, the projector needs to be placed at a distance corresponding to the screen.
According to different models, the relationship between the screen size and the projection distance is different.
9. Projection distance
Refers to the distance between the projector lens and the screen.
10. Uniformity
Refers to the ratio of the middle brightness of the cast screen to the surrounding brightness. The middle is generally defined as 100%.
11. Lens
F is the transmittance of the lens. The smaller F, the better the lens' light transmission.
Is the magnification ratio of the lens. 77/55 = 1.4, that is to say, at a fixed position, the picture can be enlarged 1.4 times.
12. Ceiling function
Hang the projector upside down to project on the roof. As shown below:
13. Rear projection function
Place the projector behind the rear screen for projection. As shown below:
14. Keystone correction
Some projectors can provide an electronic keystone correction function, which can easily correct the trapezoidal distortion of the screen caused by overhead shooting or ceiling projection.
15. Horizontal scanning frequency
Also called line frequency. The horizontal scanning frequency of the projector has a range. If the horizontal scanning frequency of the input signal from the computer exceeds this range, the projector cannot be turned on (NO SIGNAL).
16. Vertical scanning frequency
Also called Zhenpin. If the vertical scanning frequency of the input signal from the computer is outside this range, the projector will not be able to operate (NO SIGNAL). Within the range, when the computer's vertical scanning frequency is set to a high value, the projection effect is good.
17. Computer input interface
Refers to the input interface of the computer display signal. The conference room model generally has two interfaces, which can be connected to two computers at the same time, and the portable model generally only has one interface.
18. Computer output interface
Refers to the output interface of the computer display signal. The monitor can be connected via this interface. If the projector does not have this interface, you can use a VGA splitter to connect the monitor.
19. Video signal
For video signals can support three standards: NTSC, PAL, SECAM
20. Standard video input
With standard video input interface (RCA). Standard video signals are encoded when output, compressed and output, and decoded when received. This will lose some signals.
21. S video input
With S video input interface (S Video). Since the S video signal does not need to be encoded and decoded, there is no signal loss, so the S video signal is of better quality than the standard video signal.
22. Audio input and output
With audio input and output interface. You can input audio signals from computers, video recorders, etc. and play them through the built-in speakers. You can also connect the power amplifier and external speakers through the audio output interface.
23. Power supply
The lower the power of the power supply, the less heat the machine generates, so that the continuous projection time of the machine is longer. In order to use safety, the projector is usually equipped with overheat protection device.
Zhejiang Lamon Technology Inc. , https://www.chairesbaby.com