Optoma Home Cinema projector 4K400STx with 4K UHD resolution. The throw ratio indicates the width of the image produced by the projector when placed at a specific distance from the screen. For example, a throw ratio of 1.3:1 means that the image will have a width of 1 meter when the projector is positioned at a distance of 1.3 meters from the screen. This is a short throw projector as it has a Throw Ratio of 0.5:1, which falls within the range of 0.40:1 to 1.10:1 that characterizes this category. Practically, this means that you can place it at a distance from half a meter to one meter from the projection surface, effectively without any obstacles, making it useful in small spaces or presentations.

The projection technology is the way in which the light from the projector's lamp is converted into an image to be projected onto a surface through the lens. This particular projector uses DLP (DMD) technology and its lamp is LED type, which has a longer lifespan but lower brightness than regular lamps, with good color performance.
This specific technology takes its name from the initials of the words Digital Light Processing, it is the most widespread projection technology and there are projectors with one or three DLP chips. The image is created when the light from the projector lamp passes through a rotating color wheel and is reflected by a chip that has hundreds of thousands of microscopic mirrors, each corresponding to a pixel. This chip is called DMD (Digital Micromirror Device). They are suitable for well-lit spaces, such as classrooms or conference rooms, and have good color performance.

The brightness and contrast, or contrast ratio, are two very important characteristics that are taken into account, along with the projection distance and maximum diagonal you want to achieve, for selecting a projector. This specific one has a brightness of 4000 Lumens and a contrast ratio of 1000000:1.
The contrast indicates the difference between the darkest and brightest parts of an image and is an indicator of image quality. The image projected by a projector with a low contrast ratio appears washed out and flat. On the contrary, with a high contrast ratio, it appears more realistic and with greater "depth".
The brightness indicates how much light the projector can deliver on a specific surface size. The general rule suggests that the "brightest" projectors should be preferred in spaces with sufficient light or multiple light sources, while the "darker" ones should be preferred in dark spaces.

• Use: Home Cinema
• Noise Level: 28dB
• Lamp Watts: 240W
• Lamp Life (Maximum): 15000hrs
• Connectivity: HDMI, RS-232, USB, VGA
• Built-in Speakers
• Weight: 3.98kg