Laser cavity pumping method and laser system thereof

A pumping method of discrete-elements solid state laser systems pumped by semiconductor laser diodes, the method comprising:

• sending a pump beam through an active medium that includes a first face to be crossed by the pump beam, and a second face to be crossed by the pump beam along a pumping axis being associated with the pump beam, the active medium being inserted in a laser cavity having a cavity propagation axis, wherein the pumping axis coincides with the cavity propagation axis inside the active medium, and is perpendicular to an optical surface met by the pump beam after crossing the first face of the active medium, wherein the optical surface is partially reflecting at a wavelength of the pump beam and non reflecting at a wavelength at which a laser beam propagates in the laser cavity,
• wherein the pump beam is focused in the volume of the active medium between two thirds of a length starting from the first face of the active medium and the second face of the active medium (area II), so that the distance of the second face from the pump beam waist position is shorter than the pump beam confocal parameter (Zr,p).

A pumping method of discrete-elements solid state laser systems pumped by semiconductor laser diodes, the method comprising:

• sending a pump beam through an active medium that includes a first face to be crossed by the pump beam, and a second face to be crossed by the pump beam along a pumping axis being associated with the pump beam, the active medium being inserted in a laser cavity having a cavity propagation axis, wherein the pumping axis coincides with the cavity propagation axis inside the active medium, and is perpendicular to an optical surface met by the pump beam after crossing the first face of the active medium, wherein the optical surface is partially reflecting at a wavelength of the pump beam and non reflecting at a wavelength at which a laser beam propagates in the laser cavity,
• wherein the optical surface is the second face of the active medium and the optical surface reflects more than 60% of the light at a wavelength of the pump beam, and the light traveling along the pumping axis is reflected on itself at the optical surface within 2 degrees tolerance.

A pumping method of discrete-elements solid state laser systems pumped by semiconductor laser diodes, the method comprising:

• sending a pump beam through an active medium that includes a first face to be crossed by the pump beam, and a second face to be crossed by the pump beam along a pumping axis being associated with the pump beam, the active medium being inserted in a laser cavity having a cavity propagation axis, wherein the pumping axis coincides with the cavity propagation axis inside the active medium, and is perpendicular to an optical surface met by the pump beam after crossing the first face of the active medium, wherein the optical surface is partially reflecting at a wavelength of the pump beam and non reflecting at a wavelength at which a laser beam propagates in the laser cavity, and
• maintaining a larger average diameter of the pump beam inside the active medium than the diameter of a fundamental laser mode TEM0,0 of the laser beam.

A pumping method of discrete-elements solid state laser systems pumped by semiconductor laser diodes, the method comprising:

• sending a pump beam through an active medium that includes a first face to be crossed by the pump beam, and a second face to be crossed by the pump beam along a pumping axis being associated with the pump beam, the active medium being inserted in a laser cavity having a cavity propagation axis, wherein the pumping axis coincides with the cavity propagation axis inside the active medium, and is perpendicular to an optical surface met by the pump beam after crossing the first face of the active medium, wherein the optical surface is partially reflecting at a wavelength of the pump beam and non reflecting at a wavelength at which a laser beam propagates in the laser cavity, and
• maintaining a ratio between a diameter D, calculated at 1/e2 of a fundamental laser mode in the active medium, and an equivalent diameter (deq), which is twice the pump beam radius at 1/e2 of the longitudinally integrated distribution Pint(r) along the longitudinal coordinate, of the absorbed pump power spatial distribution, less than or equal to 0.8.

A pumping method of discrete-elements solid state laser systems pumped by semiconductor laser diodes, the method comprising:

• sending a pump beam through an active medium that includes a first face to be crossed by the pump beam, and a second face to be crossed by the pump beam along a pumping axis being associated with the pump beam, the active medium being inserted in a laser cavity having a cavity propagation axis, wherein the pumping axis coincides with the cavity propagation axis inside the active medium, and is perpendicular to an optical surface met by the pump beam after crossing the first face of the active medium, wherein the optical surface is partially reflecting at a wavelength of the pump beam and non reflecting at a wavelength at which a laser beam propagates in the laser cavity,
• maintaining a larger average diameter of the pump beam inside the active medium than the diameter of a fundamental laser mode TEM0,0 of the laser beam, and
• using a pump source, whose transverse distribution is radially symmetrical with respect to the pumping axis of the pump beam, and a crystal with a length ranging from 1 to 3 times the pump beam confocal parameter, in order to obtain laser beam qualities ranging between M2=1.3 and M2=2.2.

A pumping method of discrete-elements solid state laser systems pumped by semiconductor laser diodes, the method comprising:

• sending a pump beam through an active medium that includes a first face to be crossed by the pump beam, and a second face to be crossed by the pump beam along a pumping axis being associated with the pump beam, the active medium being inserted in a laser cavity having a cavity propagation axis, wherein the pumping axis coincides with the cavity propagation axis inside the active medium, and is perpendicular to an optical surface met by the pump beam after crossing the first face of the active medium, wherein the optical surface is partially reflecting at a wavelength of the pump beam and non reflecting at a wavelength at which a laser beam propagates in the laser cavity, and
• providing for changing a position of the pump beam focus or a wavelength of the semiconductor laser diodes.