Barrier member for a telescope

A telescope, comprising:

• a lens barrel for bearing an optical system;
• an optical system moving mechanism for moving said optical system between a position of non-use and a position of use;
• and
• a barrier member movable to a position of protection at which it protects a front surface of said optical system, or a position of withdrawal at which it has withdrawn from the front surface of said optical system, operatively connected to said optical system moving mechanism, said barrier member being moved between said position of protection and said position of withdrawal responsively to a manipulation performed on said optical system moving mechanism,
• wherein when said optical system is thrust from said position of non-use to said position of use, said barrier member is pressed by said lens barrel bearing said optical system and moved from said position of protection to said position of withdrawal.

A telescope, comprising:

• a lens barrel for bearing an optical system;
• an optical system moving mechanism for moving said optical system between a position of non-use and a position of use;
• and
• a barrier member movable to a position of protection at which it protects a front surface of said optical system, or a position of withdrawal at which it has withdrawn from the front surface of said optical system, operatively connected to said optical system moving mechanism, said barrier member being moved between said position of protection and said position of withdrawal responsively to a manipulation performed on said optical system moving mechanism,
• wherein said optical system moving mechanism moves said optical system between said position of non-use and said position of use, serves as a focusing mechanism that displaces a focal position of said optical system when said optical system lies at said position of use, wherein said barrier member is moved with an initial manipulation performed on said optical system moving mechanism, and wherein the focal position of said optical system located at said position of use is displaced with another manipulation performed thereon.