Mode matching optical system of Green Lock System

Last modified : 2017/09/04


Target beam parameter

Y-axis

Mirror

q-parameter

waist radius [mm]

beam radius [mm]

qx

qy

W0x

W0y

Wx

Wy

SR2 (AR-surface)

1.141436 + 0.026444i

1.145506 + 0.026587i

0.066919

0.067099

2.889234

2.891750

SR2 (HR-surface)

1.485931 + 0.040023i

1.488242 + 0.040171i

0.082325

0.082478

3.057627

3.056715

SR3 (Input)

12.597431 + 0.040024i

12.599742 + 0.040171i

0.082325

0.082478

25.912690

25.869443

BS (HR-surface)

-1017.395806 + 291.640196i

-1017.396204 + 291.640312i

7.027560

7.027562

25.503215

25.503220

ITMY (HR-surface)

-1500 + 774.596669i

11.452985

24.961202

ETMY (HR-surface)

1500 + 774.596669i

11.452985

24.961202

X-axis

Mirror

q-parameter

waist radius [mm]

beam radius [mm]

qx

qy

W0x

W0y

Wx

Wy

PR2 (AR-surface)

1.179513 + 0.026317i

1.181989 + 0.026422i

0.066757

0.066891

2.992774

2.993064

PR2 (HR-surface)

1.530937 + 0.039779i

1.533251 + 0.039928i

0.082075

0.082228

3.159777

3.158650

PR3 (Input)

12.597037 + 0.039779i

12.599351 + 0.039928i

0.082075

0.082228

25.991002

25.947259

BS (HR-surface)

-1024.352272 + 292.664734i

-1020.788469 + 291.640312i

7.039893

7.027562

25.626193

25.581808

ITMX (HR-surface)

-1500 + 774.596669i

11.452985

24.961202

ETMX (HR-surface)

1500 + 774.596669i

11.452985

24.961202


Mode matching optical system

Conditions

・ Waist radius of the beam from the fiber coupler = 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)

Mode matching optical system (back of SR2)

Mirror

q-parameter

Waist radius [mm]

Beam radius [mm]

qx

qy

W0x

W0y

Wx

Wy

Fiber coupler

0 + 0.723393i

0.350

0.350

L1 (Input)

0.220 + 0.723393i

0.350

0.365828

L1 (Output)

-0.108344 + 0.015935i

0.051947

0.356989

L2 (Input)

0.759858 + 0.016086i

0.051947

2.199920

L2 (Output)

-0.865307 + 0.026488i

0.066974

2.188928

SR2 (AR)

1.143693 + 0.026488i

0.066974

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

Y-axis Beam radius Y-axis Beam radius


Pattern B (3 lenses)

Mode matching optical system (back of SR2)

Mirror

q-parameter

Waist radius [mm]

Beam radius [mm]

qx

qy

W0x

W0y

Wx

Wy

Fiber coupler

0 + 0.723393i

0.350

0.350

L1 (Input)

0.089 + 0.723393i

0.350

0.352639

L1 (Output)

0.108858 + 0.016086i

0.052192

0.357035

L2 (Input)

0.759858 + 0.016086i

0.052192

2.465986

L2 (Output)

0.434746 + 35.905184i

2.465809

2.465990

L3 (Input)

1.019746 + 35.905184i

2.465809

2.466803

L3 (Output)

-0.973312 + 0.026619i

0.067139

2.455838

SR2 (AR)

1.143688 + 0.026619i

0.067139

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

Y-axis Beam radius Y-axis Beam radius


Back of PR2


Lens displacement

Y-axis

Pattern A (2 lenses)

GreenModeMatch_2lens_170904.pdf


Pattern B (3 lenses)

GreenModeMatch_3lens_170904.pdf


X-axis