When you regularly make presentations to your employees, or clients or others who visit your office, having an overhead projector in the office can make a significant difference in the effectiveness of the presentation. No more crowding around one small computer screen or using cumbersome dry erase boards or even sheets of paper. With the right overhead projector, your presentation appears in crisp, clear detail on a large screen (or blank wall in some cases), making it easier for everyone to see the information.
Overhead projectors are generally a major purchase, though – even small projectors for home or small office use are expensive – so before you bust the budget purchasing the wrong machine, you need to learn about the various types of projectors and the features you should look for, to prevent wasting money on something that won’t work for your needs.
DLP or LCD?
The most common types of overhead projectors are DLP, or Digital Light Processing, or LCD, Liquid Crystal Display. DLP projectors work when light is shined into a tiny chip with thousands of mirrors embedded inside; each mirror reflects one pixel of the image through the projector lense onto the screen. While the projector lamps in DLP projectors tend to burn hot, and need to be cooled down regularly to maintain their life, most quality lamps will last for up to 60,000 hours of use.
LCD projectors, on the other hand, are better for those who will only use the projector for a few hours each day; the lamps are usually rated for about 2,000 hours of use. LCD projectors work by streaming electrical charges to the blue, green and red pixels embedded in the screen. When the charge hits the pixels, they open to let light in and create the display.
In general, LCD projectors produce sharp, detailed images with a high level of color saturation, while DCP projectors offer better contrast.
Contrast, Brightness and Other Concerns
Once you’ve determined which type of projector you want to buy, compare models by considering their cost, weight, resolution, brightness, contrast and other factors. It might be tempting to choose the smallest or least expensive model, but without considering these factors, you could end up disappointed.
Resolution is important, because you need a projector that is capable of producing clear images on a larger screen. The higher the resolution, the clearer the image will be. You see resolutions described in numbers and acronyms; for your business use, look for a resolution of at least SXGA 1280 x 1024. This resolution allows for clear presentations and detail. Anything smaller and small details will be difficult to see or blurry.
You also want to make sure your projector offers sufficient brightness, making images easier to see. In general, for business use, a projector with 2,000-3,000 lumens is sufficient. If you’ll be using the projector in a room with the lights on, or with lots of windows, look for a model that offers more lumens.
The brightness of the projected image is often influenced by the projector lamps and the projector bulbs being used. Most projectors allow you to use incandescent bulbs, which offer about 2,000 hours of life, while LED bulbs offer up to ten times that amount. LED bulbs are more expensive upfront, but don’t need to be replaced as often.
Finally, consider the contrast ratio of the projectors you’re comparing. The better the contrast ratio, the more clear and defined the images on the screen will be. Look for a projector with a high static contrast ratio to ensure that you get the crispest images possible.
Many projectors offer additional features, such as automatic shutoff, or “eco-mode,” which improves the lamp life while reducing energy usage. Once you know what type of projector you’re looking for, compare the additional features on the model to see which will
be most effective for your needs and business.
Taking the time to compare overhead projectors and research the one that best meets your needs will save you both time and money in the long run. While it may be tempting to choose the least expensive model, if the projector doesn’t do what you need it to do, it’s a wasted purchase – and no one has the time for that.