Data and Video Inputs / Outputs
Connectivity and compatibility are important factors into the sharpest, clearest images. Below is a list of the many different inputs and outputs you will find on projectors on the market today.
BASIC TYPES OF PORTS
Analog
RCA Composite Port - Used for connecting your projector to older style devices including VCRs and camcorders, RCA Composite Video produces the lowest resolution at 200-220p. Due to the low resolution that RCA composite video provides, it should be used only if your source device does not offer S-video or Component video outputs. This port does support EDTV or HDTV resolutions
S-Video Port - The S-Video port is used to connect to a video source’s output port. While approximately twice the resolution of Composite Video, S-Video does not provide the definition and clarity that the VGA, M1, DVI, HDMI or Component ports do. S-Video connectors are keyed and will only fit in one direction. Audio is carried through a separate audio port.
RGB-IN Ports - Other names include VGA connector, D-sub 15, mini sub D15 and mini D15). Inputs and output ports are always female so choose a male-to-male cable to connector your projector to a computer or other VGA source device. VGA has various iterations and styles including VGA, SVGA, SXGA, and UXGA, which define the maximum resolution.
Another key benefit here is if you have more than one presenter than these ports will allow you to connect more than one computer to your projector. This is great because it allows one person to set up their presentation while the other is presenting.
RGB-OUT Port - The VGA Video Input Port is for connecting a source device to your projector. The same applies to the output as the input above so choose a male-to-male cable to connect your projector to your computer or other VGA type source.
A key benefit with this port is if you need the video from your computer to be seen on the projector and on a monitor at the same time, the RGB-OUT port will allow you to connect a separate external monitor to your projector.
Component Video (Y, R-Y, B-Y, or YPbPx) - The Component Video In Port is used for connecting your projector to a DVD player, HDTV tuner, digital cable box, or digital satellite box. The signal is transmitted directly from your source device into the projector. Component video supports High Definition signals up to 720p, and provides a much better picture than S-video or RCA composite video.
Digital
M1 Digital Video and Control Port - The M1 connector is also known as “EVC” or “P&D” (Plug & Display) connector. M1 is an interface designed for display devises. It is most often found on projectors, and it can receive a variety of signals – analog video (VGA), digital video (DVI and HDMI) and even USB. The M1 also supports EDTV and HDTV resolutions.
The M1 interface closely resembles a DVI connector. It uses a 30-pin (3 rows of 10 pins) LFH connector, with an offset ground bar. For cables that carry and analog video signal, there are additional pins surrounding the ground bar.
HDMI – HDMI is a new type of cable connection (see image) that is used to connect and output device such as a DVD player, Bluray player, HDDVD player, gaming console, digital satellite box, or digital cable box. HDMI connections transmit both digital video and audio and support all HDTV resolutions including 720p, 1080i, and 1080p. Since HDMI and DVI use the same method to transfer video, you can connect a device with HDMI and a device with DVI with an HDMI to DVI cable. However, using an HDMI to DVI cable will not carry audio signals since DVI is purely a video connection. An HDMI connection is the simplest way to reduce cable clutter and provide the best picture and sound for high definition content.
DVI Digital Video Port - The DVI (Digital Visual Interface) Port is used to connect your projector to a DVI-enabled computer, DVD player, digital satellite or cable TV box, or any device with a DVI-out port. DVI supports all HDTV resolutions including 720p, 1080i, and 1080p and carries video signals only (no audio). DVI is offered in DVI-D, which is only digital, and DVI-I, which supports analog and digital signals. Projectors have DVI-D ports, so ensure the cable you purchase is a DVI-D cable.
RS 232 Serial Port – The RS-232 serial input connector is for transmitting data to the projector. This is most often used for controlling the projector with a computer and calibrating it with any included software. The connector most often seen on projectors accepts 6 pins whereas serial connectors on a computer generally accept 9 pins. A 6-pin to 9-pin RS-232 serial cable is usually needed when connecting a device to the serial port of a projector.
USB Port - This connector is very versatile and used for transmitting data, however it is only present on a few projector models at the time of writing. A USB connection also comes in different sizes. The one pictured is a USB-B connector whereas the USB connectors you see on computers are typically USB-A connectors. These two USB connectors are compatible. Projectors that do have a USB connection can be used to display pictures from a flash drive, videos from an iPod, or can even be used with a USB hub to connect multiple sources at once. Since this is not a feature on every projector you may need to consult the projector’s user manual or manufacturer’s website for details and capabilities of the USB.
LAN - This connection allows the projector to access network content, this is a fairly new feature and not available on most projectors. Expect to see wireless solutions in the near future.
Audio
Audio-IN - If you want your audience to hear sound that is part of your presentation or video recording, you’ll want to have this. It sends audio data from your computer, VCR, or DVD player to the projector.
Audio-OUT - If you are in a large room and need more sound, you may need to hook up to an external sound system. Audio-Out sends audio data from your projector to an external sound system.
RCA Audio Port - The RCA Audio Port on your projector is used to connect the source device’s audio output to play sound through the projector’s speaker. While perfectly suitable for small presentations, the audio out from your source device should be connected to a receiver for the best stereo sound.
Audio Mini-Jack - This connector is used for transmitting stereo audio. Some projectors and devices may have two of these jacks, one for input and one for output. The only major difference between an audio mini jack and a 3.5mm audio jack is the size of the connectors. An audio mini jack is smaller than a 3.5mm audio jack.
3.5mm Audio Port - This port is used to connect the audio out from your computer’s sound card to the projector so that sound plays through the projector’s speakers. Suitable for small presentations, the projector’s speakers are typical not ideal for larger scale productions or for home theater applications.
Other I/O
12 Volt Trigger - Some projectors output 12 volts, which will trigger the electric projection screen to lower and raise when the projector is switched off.
HDMI External Expansion - Allows for additonal HDMI inputs.
IR Port Extension / IR Emitter - If you plan on mounting the projector behind and on the ceiling you will not be able to use an IR remote unless you stand up in front of it and turn around, which would not be a good thing. This handy input jack allows you to plug either an IR emitter cable from either an IR repeater system or RF base station directly into it. You then run the sensor for an IR system to a place in front of your sitting area or in the case of RF anywhere as a line of site to the sensor is not important in this situation.
Having a dedicated port, for an IR jack, is a nice feature, but not necessary. You can use an IR repeater or RF remote and use an IR emitter that sticks right on to the front of the IR “eye” on your projector.