The Logitech TV Cam has a maximum video resolution of 1280 x 720 pixels. That's over three times the video resolution of a 640 x 480 pixels webcam, which is the most common video resolution. Across all webcams of this type and age the worst video resolution is 640 x 480 pixels and the best is 1920 x 1080 pixels.
There are a number of alternative webcams that have a video resolution of 1280 x 720 pixels currently available that you might also want to look at including the Logitech C920 which has a better Rating.
If the video resolution of this webcam is not high enough for you then you might want to consider the Logitech BCC950 (£149.99) (1920 x 1080).