ruling pen การใช้

• Its technology virtually replaced the ruling pen and greatly simplified technical drawing.
• A ruling pen contains ink in a slot between two flexible metal jaws, which are tapered to a point.
• In the Soviet Union, ruling pens were widely used by women for eyebrow hair removal, being used as tweezers.
• In the 17th century, a stylus that could draw a line with a specific width called a ruling pen was developed.
• Ink lines were drawn with a ruling pen, a relatively sophisticated device similar to a dip-in pen but with adjustable line width, capable of producing a very fine controlled line width.