HDMI splitters (and graphics cards) can send a single video signal to two HDMI monitors at the same time.
Can I use an HDMI splitter to extend not duplicate my laptop screen across two monitors?
An HDMI splitter can’t extend the display to two monitors. What a splitter does is mirror the original image to 2 or more displays. A USB-to-HDMI adapter may effectively add a second HDMI port, which will extend the display. However, not all computers are able to output to a display via a USB port.
How do I connect 2 monitors to my laptop with HDMI splitter?
HDMI Splitter Just plug the single USB end into your computer’s HDMI port, and plug each of your two monitors into each of the two HDMI ports at the other end of the adapter.
What type of splitter do I need for dual monitors?
Active splitters allow you to connect multiple monitors to a single video source, while passive splitters allow you to connect multiple video sources to a single monitor.