The brighter, the better

Measured in Ansi lumens, the brightness level gives you an idea of a projector's power.

As a rough guide, you need a projector with a lumens level that is in the thousands for an auditorium. A model with around 200 lumens is good enough for a classroom or small conference room.

Go light

If you are always on the move, get something light and portable.

Last year, projector makers like Optoma and 3M introduced a new category of image casters called pico projectors.

At under 200g, these mini projectors fit in the palm of your hand or in your pocket.

The trade-off is that they have lower lumens levels and do not project as much image detail as their full-sized counterparts.

Know the tech

There are three main projection technologies to date.

Liquid crystal display (LCD), digital light processing (DLP) and liquid crystal on silicon (LCOS).

The science behind projection involves the creation of tiny pixels of light and combining them to create an image.

In LCD projectors, light passes through layers of charged crystals to form an image.

In DLP, a tiny panel containing millions of tiny mirrors is used instead. Each mirror forms a pixel of an image and by moving rapidly when light hits it, it turns the pixel on or off. A colour filter then adds colour to the image.

LCOS combines both LCD and DLP intelligence for high-resolution images with true-to-life colours.

Shorter throw ratio

This refers to how near you can place a projector to the screen and still have a large image.

A good projector can be placed, say, 1m from the screen (or wall) and still project a clear image.

So, at the same distance from the screen, a projector with a shorter throw ratio will give you a larger screen size compared to one with a longer throw ratio.

Higher contrast ratio

A projector with a higher contrast ratio can display deeper blacks and purer whites.

This is an important consideration for video playback as it affects the way colours show up on screen.

Check connection ports

You would want your projector to work with a variety of devices.

All projectors should have at least a VGA port that allows you to connect it to a laptop.

If you want to hook it up to a DVD player, ensure that there is at least a connection for S-Video, composite video or component video.

Pricier models may also offer high-definition multimedia interface (HDMI) slots for devices such as a Blu-ray player.

Check for plug-and-play ease

Higher-end models come with intuitive smarts like DisplayLink, which allows easy plug-and-play via a USB cable.

Advanced models may include functions such as LitePort PC-free presenter. This allows users to project content directly from a USB flash drive.

This story was first published in The Straits Times Digital Life.

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