[Choose projection screen, rear projection or front projection is suitable] Engineering projection screen
The color reproduction quality of the rear projection is mostly better than that of the front projection
The color reflected by the front projection screen is related to the quality of the screen material. Because the front projection material is an opaque reflective material, the brightness of the projector and its color reproduction accuracy are also factors that affect the true color reproduction. This is the same for rear projections. However, David Hill said: 'Because the rear projection is transparent, the color reproduction quality of the rear projection is better than that of the front projection.'
HowardSinkoff said: 'Whether it is a front projection or a rear projection, the color reproduction accuracy depends on the screen surface and the brightness of the ambient light.' Whether it is a front projection or a rear projection, if the screen gain is the same, the color reproduction accuracy must be the same. . The color reproduction accuracy has nothing to do with front projection or rear projection. However, the ambient light of the front projection is not easy to control, and the rear projection is easy to control the ambient light. Therefore, generally speaking, the color reproduction quality of the rear projection is better than that of the front projection. In addition, from the perspective of the screen, the silver screen has the best color reproduction ability; the white screen has the second best color reproduction ability; the gray screen has the worst color reproduction ability.
Anjum said: Because the rear projection means that the projector is behind the screen, a space must be reserved for the projector when designing the rear projection scheme. This is called a black room or a room behind the screen. The requirement for a black room must be nothing else. Affected by the ambient light, that is, completely black. Because if there are ordinary ambient light in the dark room, these ambient light will affect the quality of the image projected on the screen. The ambient light has a great influence on the contrast and brightness of the projected image. When you choose the rear projection solution If you ensure that the dark room is not affected by ambient light, the audience will see very uniform image brightness and high contrast. To obtain a good projection image, it is necessary to ensure that the uniform projection brightness is obtained, and the image is clear, bright, and colorful.
The cost of establishing a rear projection system is higher than that of the front projection
When setting up a demonstration system in a specific place, the owner of this system must definitely consider; in this occasion, is it better to use rear-projection demonstration or front-projection demonstration? Of course, this is a matter of budget.
First choice, if Le has a small budget, your choices will be limited. If you just want a good presentation effect, then rear projection may be the best solution (except for movies). In different presentation occasions, you have to use different presentation solutions, such as outdoor or indoor? Do you want to make a presentation in a sports field or a conference room? Or a demonstration in the banquet hall? The final plan may vary.
DavidHull believes: 'Because the screen materials used in the rear projection system are higher than those used in the front projection, and the technical indicators achieved are higher, the cost of building a rear projection system is higher than that of the front projection. The rear projection screen materials are more refined. , To ensure that light and images can penetrate the screen and produce high-quality images.'
What is the total cost difference between front projection and rear projection? Anjum said: 'In fact, the rear projection is not twice or ten times more expensive than the front projection. The price of the rear projection is only a little bit higher than the front projection solution. If the screen size is the same, if the cost of a set of front projection is 100 yuan, The whole set of rear projection system only costs about 130 to 140 yuan. Generally, if you want to achieve the same image quality, the rear projection is 25% more expensive than the front projection. The reason for this 25% cost is not only the screen, but also the projector Lens, etc. From the perspective of the total budget, you may be more clear. If you decide to use the front projection, you must control the indoor lighting system, which may take a lot of effort. The work and lighting of the AV audio-visual company The system doesn’t matter much. The audio-visual company may require the system owner to control the lighting. In this way, there may be an extra layer of things to consider, because he has to ask a group of people to do the lighting design. If a rear projection solution is adopted , You don’t need to pay special attention to the lighting system.'
StevieNg said: The cost of the front projection system is relatively cheaper than that of the rear projection system.
Compared with the screen alone, the front projection screen is much cheaper, because the rear projection system needs to add mirrors and other equipment in order to shorten the projection distance, and the cost is more expensive than the front projection. In terms of installation methods, it is much more expensive: first of all, the installation process of fixing the screen and having a screen is already expensive. It also includes building renovation and room area. The current city is an inch of land and an inch of gold. If a few square meters of space are used as a rear-projection darkroom, the cost will increase invisibly. If you just place a projector directly behind the screen for rear projection, the reflection system can be omitted, but the space required is even greater. Cheap price This is the advantage of front projection over rear projection.
Of course, if you want to achieve the same projection screen effect, the front projection is not cheap, because the front projection needs to use a much more expensive projector to obtain the same projection screen as the rear projection.