Laser pumping device and system including geometric light concentrator and thermal insulator

A laser pumping device, comprising:

• a pump-light source, configured to emit a pump light;
• a dielectric block with a pump axis, comprising a first surface, a second surface, and a plural number of reflection surfaces, wherein the first surface is a planar surface, the dielectric block is configured to receive the pump light into the first surface, guide the pump light along the pump axis surrounded by the reflection surfaces, and transmit the pump light toward the second surface, and oppositely faced two of the reflection surfaces are wedged with a down-tapered aperture perpendicular to the pump axis;
• and
• a laser gain material, installed at a position next to the second surface close to the pump axis and configured to receive and absorb the pump light emitted from the second surface;
• wherein a length L of the dielectric block along the pump axis is calculated from
• L
• =
• ∑
• i
• =
• 1
• N
• x
• i
• ,
• where
• ⁢
• x
• i
• =
• d
• i
• ⁢
• tan
• ⁡
• (
• θ
• +
• (
• 2
• ⁢
• i
• -
• 1
• )
• ⁢
• α
• )
• 1
• -
• tan
• ⁢
• α
• ⁢
• tan
• ⁡
• (
• θ
• +
• (
• 2
• ⁢
• i
• -
• 1
• )
• ⁢
• α
• )
• ⁢
• and
• ⁢
• d
• i
• =
• d
• i
• -
• 1
• +
• 2
• ⁢
• x
• i
• -
• 1
• ⁢
• tan
• ⁢
• α
• ,
• d
• 0
• =
• d
• ,
• d
• N
• =
• D
• ,
• θ
• ≥
• θ
• C
• with α being a wedge angle, θ being the last incident angle of the pump light on the oppositely faced two reflection surfaces, θc being a critical angle of total internal reflection for the dielectric block, D being a width of the first surface, d being a width of the second surface, and N being a maximum integer number of i subject to a maximum ith width section di=D at the first surface.