• Business projectors are mostly used for presentations, seminars, or classrooms, and are designed to produce static images like the slides and graphs in PowerPoint. These projectors are also known as “multimedia” or “data projectors”, and have an HDMI port which can be connected to a laptop. Most of these have wireless projection and multiple inputs, which make it easier to connect them to computers and laptops.

• Home theater projectors are known for high-quality images, proper contrast, and rich color saturation. These projectors give a feel of the movie theater--it is best to install them in a dedicated place where you can control the amount of outside light.

• Pico or pocket-sized projectors are so compact that you can carry them in your briefcase and hold them in your hands. They are extremely handy and are ideal for off-site meetings. They are perfect for small gatherings.

• Large venue projectors: These projects are perfect for a large audience in stadiums, worship halls, and lecture halls. They are the brightest among the projectors available in the market, but they are not portable and cannot be carried everywhere. It can be installed with a multimedia projector to enhance the quality of the image. 

After going through thousands of projector reviews, we found that most users look for these three qualities when it comes to buying the projector:

• Desirable features: For ease of installation and hassle-free projection, you should look for certain features like HDMI, which allows easy and instant digital connectivity. Other features, such as image correction, which helps to rectify a skewed image or wireless capacity for projecting without cables, are quite useful.

• The technology used: The main technologies that are used in projectors are DLP (=Digital Light Processing) and LCD (= Liquid Crystal Display). Both are good, but DLP gives a soft smooth image which is preferable for video applications. The LCD projectors are more appropriate for computer/data applications because they produce bright and sharp images.

• Warranty: There is a different warranty policy for each brand of projector. It is better to pay a little extra if you know that the manufacturer of your projector will respond to your distress call and solve any problems within 24 hours. 

• Consider the throw ratio: The throw ratio is defined as the ratio of the distance from the projector's lens to the screen (called “the throw”), divided by the screen width. A larger throw ratio means a more focused optical system. It helps you gauge how wide the image will be if you place the projector at a specific distance from the screen. If you want to permanently install the equipment, it is imperative that you calculate the throw ratio. In the event that you have a space constraint, you may select a short throw projector, which will allow you to place the projector quite close to the screen but will still display a wide enough image.

• Check the screen size: A rule of thumb for calculating the screen size of the projector is to calculate the distance of the “least-favored viewer”--that is, the distance of the person farthest from the screen--and multiply it by 1/5. For example, if the person is sitting 50 feet away from the screen, the screen size will be 10 feet high.

• Estimate how much ambient light is needed: The image should be clear and bright enough to be seen by all viewers. Under ideal conditions, a projector should be used in a dark room, because the more light means the lower will be the contrast, which will completely destroy the image. 

Epson: Epson, one of the leading manufacturers of projectors in the world, is known for cost-effective machines which boast of a number of useful features, such as high-quality images and the inclusion of latest technology.

Viewsonic: Three things define the high-quality projectors of Viewsonic: 1) color accuracy, which offers a more varied color range than conventional DLP projectors, 2) best overall projector warranty, and 3) smart design.

Source: https://www.bhphotovideo.com/explora/video/buying-guide/projectors

http://www.bestbuy.com/site/buying-guides/projector-buying-guide/pcmcat342500050003.c?id=pcmcat342500050003

http://www.toptenreviews.com/electronics/articles/home-theater-projector-tips/

http://www.purple-cat.co.uk/projector-guide

http://in.pcmag.com/projector/54041/guide/the-best-projectors-of-2016