FIG. 1 is a bottom, front and left side perspective view of a portable monitor showing my new design;
FIG. 2 is a bottom, rear and right side perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof;
FIG. 9 is an enlarged view of portion 9 in FIG. 2; and,
FIG. 10 is an enlarged view of portion 10 in FIG. 2.
The broken lines in the drawings illustrate portions of the portable monitor which form no part of the claimed design. The diagonal lines in the drawings represent reflective surfaces. The dot-dash broken lines in the drawings depict boundaries of the enlarged portions and form no part of the claimed design.