This question most often is asked by instructors wanting to increase the precision of the meterstick to include 1 cm tickmarks instead of 10 cm tickmarks.
The only way to do this is to increase the size of the video to full-screen using the icon in the bottom-right of the video player.
If after full-screening the video this doesn't increase the precision of the meterstick, then unfortunately nothing else can be done.
The Pivot Interactives video player "draws" a meterstick on your screen based on the calibration you give as well as on your specific display. This is done because it's the only way to have an accurate meterstick display on any size of display. What this also means is that if your display is too small, then the tickmarks of the meterstick would be too close together to actually be useful. It would be like zooming in too close on a digital image; at a certain point, it all just looks too blurry to be discernable.