PASCO OS-9256A - Manuals

Precision Interferometer 012-07137A 2 Equipment The OS-9255A Precision Interferometer includes the following equipment: • 5 kg Base with built-in micrometer• Adjustable Mirror• Movable Mirror• Beam Splitter• Compensator Plate• (2) Component Holder• Viewing Screen• Lens, 18 mm Focal Length• Diffuser•...

Precision Interferometer 012-07137A 4 Interference Theory A beam of light can be modeled as a wave of oscillating electric and magnetic fields. When two or more beams of light meet in space, these fields add according to the principle of superposition. That is, at each point in space, the electric a...

5 012-07137A Precision Interferometer In this way the original beam of light is split, and portions of the resulting beams are brought back together. Since the beams are from the same source, their phases are highly correlated. When a lens is placed between the laser source and the beam-splitter, th...

Precision Interferometer 012-07137A 6 The Fabry-Perot Interferometer In the Fabry-Perot Interferometer, two partial mirrors are aligned parallel to one another, forming a reflective cavity. Figure 4 shows two rays of light entering such a cavity and reflecting back and forth inside. At each reflecti...

7 012-07137A Precision Interferometer OS-9255A PRECISION INTERFEROME -5 0 5 10 15 25 30 ADJUSTABLE MIRROR MICHELSON, TWYMAN-GREEN BEAM SPLITTER MICHELSON COMPENSA TO R MICHELSON 18 mm FL LENS VIEWING SCREEN MICHELSON, TWYMAN-GREEN 1 div = ➤ NOTE: For ease of installation the placement of the individ...

9 012-07137A Precision Interferometer 5. The slip ring at the base of the micrometer knob adjusts the tension in the dial. Before making a measurement, be sure the tension is adjusted to give you the best pos- sible control over the mirror movement. Calibrating the Micrometer For even more accurate ...

Precision Interferometer 012-07137A 10 Sources of Experimental Error Backlash— Although PASCO's carefully designed mirror movement reduces backlash considerably, every mechanical system is susceptible to backlash. However, the effects of backlash can be practically eliminated by using proper techniq...

11 012-07137A Precision Interferometer OS-9255A PRECISION INTERFEROMETER -5 0 5 10 15 25 30 ADJUSTABLE MIRROR MICHELSON, TWYMAN-GREEN BEAM SPLITTER MICHELSON COMPENSA TO R MICHELSON 18 mm FL LENS VIEWING SCREEN MICHELSON, TWYMAN-GREEN 1 div = 1 MICRON Experiment 1: Introduction to Interferometry Fig...

Precision Interferometer 012-07137A 12 6. Record d m , the distance that the movable mirror moved toward the beam-splitter according to your readings of the micrometer knob. Remember, each small division on the micrometer knob corre- sponds to one µm (10 - 6 meters) of mirror movement. 7. Record N, ...

13 012-07137A Precision Interferometer Experiment 2: The Index of Refraction of Air EQUIPMENT NEEDED: – Basic Interferometer (OS-9255A)– Laser (OS-9171)– Laser Alignment Bench (OS-9172)– Interferometer Accessories (OS-9256A) Rotational pointer, Vacuum cell, Vacuum pump Introduction In the Michelson ...

Precision Interferometer 012-07137A 14 4. Be sure that the air in the vacuum cell is at atmospheric pressure. If you are using the OS-8502 Hand- Held Vacuum Pump, this is accomplished by flipping the vacuum release toggle switch. 5. Record P i , the initial reading on the vacuum pump gauge. Slowly p...

15 012-07137A Precision Interferometer OS-9255A PRECISION INTERFEROMETER -5 0 5 10 15 25 30 ADJUSTABLE MIRROR MICHELSON, TWYMAN-GREEN B E A M S P LI TT E R M IC H E LS O N C O M P E N S AT O R M IC H E LS O N 18 mm FL LENS VIEWING SCREEN MICHELSON, TWYMAN-GREEN 1 div = 1 MICRON Experiment 3: The Ind...

Precision Interferometer 012-07137A 16 Data Analysis In principle, the method for calculating the index of refraction is relatively simple. The light passes through a greater length of glass as the plate is rotated. The general steps for measuring the index of refraction in such a case is as follows...

17 012-07137A Precision Interferometer Twyman-Green— Twyman-Green operation gives students a quick, qualita- tive look at how interferometry can be used to test optical components. See Twyman-Green Mode in the Setup and Operation section of the manual. Any distortion of the circular fringe pattern i...

Precision Interferometer 012-07137A 18 ä IMPORTANT — The Vacuum Cell is not designed to be heated. Index of Refraction for Gases— Measure the indices of refraction for various gases. Caution: The PASCO Vacuum Chamber is NOT designed to hold positive pressures. You will need to provide your own gas c...

19 012-07137A Precision Interferometer Replacement Parts Component Part No. Interferometer Base 003-05137 Adjustable Mirror 003-03957 Beam-Splitter 003-03956 Movable Mirror 003-03955 Component Holder 003-05161 Compensator 003-03958 Interferometer Manual 012-05187 Vacuum Pump OS-8502 Component Part N...

Precision Interferometer 012-07137A 20 Experiment 1: Introduction to Interferometry Teacher's Guide Reference to – Analysis (Part II) 1. The laser we used was unpolarized, and does not seem to change polarization with time. 2. No, there was no change. This would support our hypothesis that the laser...

21 012-07137A Precision Interferometer Experiment 2: The Index of Refraction of Air Reference to – Procedure 1. The chamber will be properly aligned when the reflec- tions off the front and back end-plates are aligned with each other and with the main interference pattern. (This alignment may actual...

Precision Interferometer 012-07137A 22 Experiment 3: The Index of Refraction of Glass Reference to – Procedure 1. The glass plate must be absolutely perpendicular to the laser for accurate measurement of the index of refrac- tion. When the plate is perpendicular, there will be a faint secondary frin...

23 012-07137A Precision Interferometer Technical Support Feedback If you have any comments about the product or manual, please let us know. If you have any suggestions on alternate experiments or find a problem in the manual, please tell us. PASCO appreciates any customer feedback. Your input helps ...