= Mode matching optical system for ALS at the side of PR2 and SR2 = Last modified : 2017/09/04 Under investigation : Which is the better of the 2 lens or 3 lens <> ------ == Target beam parameter == === For Y-arm === ||<|2>Mirror||<:-2>q-parameter||<:-2>waist radius [mm]||<:-2>beam radius [mm]|| ||<:>q,,x,,||<:>q,,y,,||<:>W0,,x,,||<:>W0,,y,,||<:>W,,x,,||<:>W,,y,,|| ||SR2 (AR-surface)||1.141658 + 0.026444i||1.145729 + 0.026587i||0.066919||0.067099||2.889797||2.892313|| ||SR2 (HR-surface)||1.485931 + 0.040023i||1.488242 + 0.040171i||0.082325||0.082478||3.057628||3.056716|| ||SR3 (Input)||12.597431 + 0.040023i||12.599742 + 0.040171i||0.082325||0.082478||25.912697||25.869453|| ||BS (HR-surface)||-1020.981427 + 292.656219i||-1017.458984 + 291.640312i||7.039791||7.027562||25.548554||25.504674|| ||ITMY (HR-surface)||<-2>-1500 + 774.596669i||<-2>11.452985||<-2>24.961202|| ||ETMY (HR-surface)||<-2> 1500 + 774.596669i||<-2>11.452985||<-2>24.961202|| === For X-arm === ||<|2>Mirror||<:-2>q-parameter||<:-2>waist radius [mm]||<:-2>beam radius [mm]|| ||<:>q,,x,,||<:>q,,y,,||<:>W0,,x,,||<:>W0,,y,,||<:>W,,x,,||<:>W,,y,,|| ||PR2 (AR-surface)||1.180362 + 0.026317i||1.182840 + 0.026422i||0.066757||0.066891||2.994930||2.995218|| ||PR2 (HR-surface)||1.530937 + 0.039779i||1.533251 + 0.039928i||0.082075||0.082228||3.159778||3.158651|| ||PR3 (Input)||12.597037 + 0.039779i||12.599351 + 0.039928i||0.082075||0.082228||25.991009||25.947268|| ||BS (HR-surface)||-1024.352551 + 292.664734i||-1020.788880 + 291.640312i||7.039893||7.027562||25.626199||25.581817|| ||ITMX (HR-surface)||<-2>-1500 + 774.596669i||<-2>11.452985||<-2>24.961202|| ||ETMX (HR-surface)||<-2> 1500 + 774.596669i||<-2>11.452985||<-2>24.961202|| ------ == Mode matching optical system == ||Conditions|| * The waist radius of the transmitted beam from the fiber = 350um (measured) * Optical path length from AR-surface of SR2/PR2 to the optical table ~ 2m * Assume CVI lenses ----- === Back of SR2 === ==== Pattern A (2 lenses) ==== {{attachment:GreenModeMatch_Y_2lens_170903.png|Mode matching optical system (back of SR2)|width="600"}} ||<|2>Mirror||<-2>q-parameter||<-2>Waist radius [mm]||<-2>Beam radius [mm]|| ||qx||qy||W0x||W0y||Wx||Wy|| ||Fiber coupler||<-2>0 + 0.723393i||<-2>0.350||<-2>0.350|| ||L1 (Input)||<-2>0.220 + 0.723393i||<-2>0.350||<-2>0.365828|| ||L1 (Output)||<-2>-0.108344 + 0.015935i||<-2>0.051947||<-2>0.356989|| ||L2 (Input)||<-2>0.759858 + 0.016086i||<-2>0.051947||<-2>2.199920|| ||L2 (Output)||<-2>-0.865307 + 0.026488i||<-2>0.066974||<-2>2.188928|| ||SR2 (AR)||<-2>1.143693 + 0.026488i||<-2>0.066974||<-2>2.892571|| ||SR2 (HR)||1.489013 + 0.040119i||1.485169 + 0.039991i||0.082425||0.082292||3.060270||3.057282|| ||ITMy (HR)||-1463.753784 + 729.531387i||-1538.350364 + 822.405327i||11.114831||11.801137||24.917463||25.031092|| ||ETMy (HR)||1536.246216 + 729.531387i||1461.649636 + 822.405327i||11.114831||11.801137||25.910643||24.066063|| {{attachment:BeamRadius_FC_ITMY_2lens_170903.png|Y-axis Beam radius|width="800"}} {{attachment:BeamRadius_FC_ETMY_2lens_170903.png|Y-axis Beam radius|width="800"}} ---- ==== Pattern B (3 lenses) ==== {{attachment:GreenModeMatch_y_3lens_170903.png|Mode matching optical system (back of SR2)|width="600"}} ||<|2>Mirror||<-2>q-parameter||<-2>Waist radius [mm]||<-2>Beam radius [mm]|| ||qx||qy||W0x||W0y||Wx||Wy|| ||Fiber coupler||<-2>0 + 0.723393i||<-2>0.350||<-2>0.350|| ||L1 (Input)||<-2>0.089 + 0.723393i||<-2>0.350||<-2>0.352639|| ||L1 (Output)||<-2>0.108858 + 0.016086i||<-2>0.052192||<-2>0.357035|| ||L2 (Input)||<-2>0.759858 + 0.016086i||<-2>0.052192||<-2>2.465986|| ||L2 (Output)||<-2>0.434746 + 35.905184i||<-2>2.465809||<-2>2.465990|| ||L3 (Input)||<-2>1.019746 + 35.905184i||<-2>2.465809||<-2>2.466803|| ||L3 (Output)||<-2>-0.973312 + 0.026619i||<-2>0.067139||<-2>2.455838|| ||SR2 (AR)||<-2>1.143688 + 0.026619i||<-2>0.067139||<-2>2.885427|| ||SR2 (HR)||1.489002 + 0.040318i||1.485159 + 0.040189i||0.082629||0.082496||3.052712||3.049731|| ||ITMy (HR)||-1461.017819 + 731.892574i||-1535.118889 + 824.885592i||11.132804||11.818919||24.856063||24.969411|| ||ETMy (HR)||1538.982181 + 731.892574i||1464.881111 + 824.885592i||11.132804||11.818919||25.921818||24.087634|| {{attachment:BeamRadius_FC_ITMY_3lens_170903.png|Y-axis Beam radius|width="800"}} {{attachment:BeamRadius_FC_ETMY_3lens_170903.png|Y-axis Beam radius|width="800"}} ----- === Back of PR2 === ------ == Lens displacement == === For Y-arm === ==== Pattern A (2 lenses) ==== [[attachment:GreenModeMatch_2lens_170904.pdf]] ---- ==== Pattern B (3 lenses) ==== [[attachment:GreenModeMatch_3lens_170904.pdf]] ----- === For X-arm ===