User:Pranav Rathi/Notebook/OT/2011/03/01/Laser Shutter .2 - Revision history

Pranav Rathi: /* Shutter */

Pranav Rathi — Sat, 17 Nov 2012 23:48:04 GMT

Shutter

←Older revision		Revision as of 23:48, 17 November 2012
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	The buildup is divided is the following categories. In the start make sure that you have a good set of screw driver, pliers, wire cutter, stripper and solder.		The buildup is divided is the following categories. In the start make sure that you have a good set of screw driver, pliers, wire cutter, stripper and solder.
	==== Shutter====		==== Shutter====
-	I will start with the choice of the motor. A 12V DC motor is a good choice because it can provide a wide ~~rang~~ of torques. The motor and the spring works against each other so it important to have the right set. So choose a 12V DC motor with a shaft length of at least 15mm. Mount the motor on the cage plate or platform as shown in the picture, you will need 4/40 screws to tight it (in present setup). ~~once~~ this is done, unscrew and take the motor out.	+	I will start with the choice of the motor. A 12V DC motor is a good choice because it can provide a wide range of torques. The motor and the spring works against each other so it important to have the right set. So choose a 12V DC motor with a shaft length of at least 15mm. Mount the motor on the cage plate or platform as shown in the picture, you will need 4/40 screws to tight it (in present setup). Once this is done, unscrew and take the motor out.

-	Now next task is to choose the right spring. The spring should be half the length of the shaft and the shaft should easily fit through the spring. I want to keep the spring-choice procedure really simple and easy. To choose the spring first need to know the torque of the motor. This is really simple, it can be mathematically ~~calculate~~ if the voltage and the current is known. But I like the experimental way; the setup is shown in the slide2. In the slide I have a DC motor with a leverage pivoted at the shaft and a free weight hanging with a string on the other side. In this, all I am doing is balancing the weigh at that point by giving the motor just enough power.	+	Now next task is to choose the right spring. The spring should be half the length of the shaft and the shaft should easily fit through the spring. I want to keep the spring-choice procedure really simple and easy. To choose the spring first need to know the torque of the motor. This is really simple; it can be mathematically calculated if the voltage and the current are known. But I like the experimental way; the setup is shown in the slide2. In the slide I have a DC motor with a leverage pivoted at the shaft and a free weight hanging with a string on the other side. In this, all I am doing is balancing the weigh at that point by giving the motor just enough power.
-	so the torque is equal to the weight at the distance from the shaft:	+	So the torque is equal to the weight at the distance from the shaft:

	*:: <math> \mathbf{\tau}=r \times F = r \times m .g </math>		*:: <math> \mathbf{\tau}=r \times F = r \times m .g </math>
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	*:: <math> \mathbf{\tau}=2{\pi}n.K.r^2 </math>		*:: <math> \mathbf{\tau}=2{\pi}n.K.r^2 </math>

-	Where K is the stiffness, r distance from the shaft center and n number of times spring twisted one complete 360 degrees circle before it was hacked. Since the torque is n dependent, it is a matter of great convenience, because now it is really easy to pick the right spring. All you have to do, is twist the required number of times before hacked to get the right restoring torque.	+	Where K is the stiffness, r distance from the shaft center and n number of times spring twisted one complete 360 degrees circle before it was hacked. Since the torque is n dependent, it is a matter of great convenience, because now it is really easy to pick the right spring. All you have to do is twist the required number of times before hacked to get the right restoring torque.

-	~~Now we are ready~~ to ~~put the the shutter together. Start~~ with ~~the motor~~, ~~most of the motors have little holes for the screws to hold slide3. Choose~~ a ~~screw which can fit into that but still sticking out few millimeters slide4. Next is the rotation stage which joins the cylinder to the~~ motor ~~and holds the~~ spring ~~assembly. I choose the wood for this function, because its easy to machine~~ and a good thermal-insulator slide5. I drilled two hole on both sides; to fit the shaft and 1/4 screw on either sides. To drill for 1/4 I used 15/64 size drill-bit slide6,7,8 & 9. Now the motor can be attached to one side of the stage and cylinder to other slide10 & 11.	+	There is even easier way to deal with mambo-jumbo, get a motor get a spring and put them together.

-	Now we ~~can machine~~ the ~~spring assembly~~. ~~Slide 12 shows~~ the ~~parts~~ of ~~spring assembly. We need two metal strips of .75 and 1 cm long with a hole in~~ the ~~end~~ for the screws. ~~This strips with the~~ screw on the motor ~~will define~~ the ~~boundaries of~~ the ~~movement~~. ~~Cylinder will rotate end~~ to ~~end between these strips~~. To ~~screw the strips directly on the stage we need to~~ drill ~~two holes~~ for ~~the screws~~. ~~The holes are 135 degree apart over~~ the ~~face~~ of the stage ~~as shown in the slide13. We also drill a small hole for the spring attachment near the edge~~.	+	Now we are ready to put the shutter together. Start with the motor; most of the motors have little holes for the screws to hold slide3. Choose a screw which can fit into that but still sticking out few millimeters slide4. Next is the rotation stage which joins the cylinder to the motor and holds the spring assembly. I choose the wood for this function, because it’s easy to machine and a good thermal-insulator slide5. I drilled two hole on both sides; to fit the shaft and 1/4 screw on either sides. To drill for 1/4 I used 15/64 size drill-bit slide6, 7, 8 & 9. Now the motor can be attached to one side of the stage and cylinder to other slide10 & 11.

-	Now all parts are ready to get together slide 14. This shutter is little different of what is shown in the video but follows the same concept. Put the shorter end of the spring in the hole on the stage like slide 15. Now the motor shaft will go through the spring into the stage. The other side of the spring is hold against the screw. You can twist the required number of turns before it holds to get the right restoring torque. Now the spring wants to move the stage clockwise but the strip against the screw does not let it (this is position 1). As the voltage is applied the motor turns counterclockwise working against the spring until the second strip stops it. When the voltage is applied the stage remains in the second position. As soon as the voltage is turned down the spring restores the stage into the previous position. These two positions can be chosen for the shutter to be on/off slide 16,17 & 18.	+
		+	Now we can machine the spring assembly. Slide 12 shows the parts of spring assembly. We need two metal strips of .75 and 1 cm long with a hole in the end for the screws. These strips with the screw on the motor will define the boundaries of the movement. Cylinder will rotate end to end between these strips. To screw the strips directly on the stage we need to drill two holes for the screws. The holes are 135 degree apart over the face of the stage as shown in the slide13. We also drill a small hole for the spring attachment near the edge.
		+
		+	Now all parts are ready to get together slide 14. This shutter is little different of what is shown in the video/pictures but follows the same concept. Put the shorter end of the spring in the hole on the stage like slide 15. Now the motor shaft will go through the spring into the stage. The other side of the spring is hold against the screw. You can twist the required number of turns before it holds to get the right restoring torque. Now the spring wants to move the stage clockwise but the strip against the screw does not let it (this is position 1). As the voltage is applied the motor turns counterclockwise working against the spring until the second strip stops it. When the voltage is applied the stage remains in the second position. As soon as the voltage is turned down the spring restores the stage into the previous position. These two positions can be chosen for the shutter to be on/off slide 16, 17 & 18.

	A fully assembled shutter is ready. Now the next task is to prepare a control box.		A fully assembled shutter is ready. Now the next task is to prepare a control box.

Pranav Rathi: /* Construction */

Pranav Rathi — Sat, 17 Nov 2012 23:20:04 GMT

Construction

←Older revision		Revision as of 23:20, 17 November 2012
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	=== Construction===		=== Construction===
-	The buildup is divided is the following categories. In the start make sure that you have a good set of screw driver, ~~players~~, wire cutter & stripper and solder.	+	The buildup is divided is the following categories. In the start make sure that you have a good set of screw driver, pliers, wire cutter, stripper and solder.
	==== Shutter====		==== Shutter====
-	I will start with the choice of the motor. A 12V DC motor is a good choice because it can provide a wide rang of torques. The motor and the spring works against each other so it important to have the right set. So choose a 12V DC motor with a shaft length of at least 15mm. Mount the motor on the cage plate as shown in the picture, you will need 4/40 screws to tight it. once this is done, unscrew and take the motor out.	+	I will start with the choice of the motor. A 12V DC motor is a good choice because it can provide a wide rang of torques. The motor and the spring works against each other so it important to have the right set. So choose a 12V DC motor with a shaft length of at least 15mm. Mount the motor on the cage plate or platform as shown in the picture, you will need 4/40 screws to tight it (in present setup). once this is done, unscrew and take the motor out.

-	Now next task is to choose the right spring. The spring should be half the length of the shaft and the shaft should easily fit through the spring. I want to keep ~~all this~~ really simple~~, so there is a very~~ easy ~~way to choose the right spring~~. To choose the spring first need to know the torque of the motor. This is really simple, it can be mathematically calculate if the voltage and the current is known. But I like the experimental way; the setup is shown in the slide2. In the slide I have a DC motor with a leverage pivoted at the shaft and a free weight hanging with a string on the other side. In this, all I am doing is balancing the weigh at that point by giving the motor just enough power.	+	Now next task is to choose the right spring. The spring should be half the length of the shaft and the shaft should easily fit through the spring. I want to keep the spring-choice procedure really simple and easy. To choose the spring first need to know the torque of the motor. This is really simple, it can be mathematically calculate if the voltage and the current is known. But I like the experimental way; the setup is shown in the slide2. In the slide I have a DC motor with a leverage pivoted at the shaft and a free weight hanging with a string on the other side. In this, all I am doing is balancing the weigh at that point by giving the motor just enough power.
	so the torque is equal to the weight at the distance from the shaft:		so the torque is equal to the weight at the distance from the shaft:
		+
	*:: <math> \mathbf{\tau}=r \times F = r \times m .g </math>		*:: <math> \mathbf{\tau}=r \times F = r \times m .g </math>

-	Once this is know we can choose the spring with less torque ~~than this~~. The restoring torque applied by the spring can also be measure in the same fashion (as motor) as shown in slide1, with hanging known weight. The spring stiffness and the torque can be related through:	+	Once this is know we can choose the spring with less torque. The restoring torque applied by the spring can also be measure in the same fashion (as motor) as shown in slide1, with hanging known weight. The spring stiffness and the torque can be related through:
		+
	*:: <math> \mathbf{\tau}=2{\pi}n.K.r^2 </math>		*:: <math> \mathbf{\tau}=2{\pi}n.K.r^2 </math>

Pranav Rathi: /* Motivation */

Pranav Rathi — Sat, 17 Nov 2012 23:12:15 GMT

Motivation

←Older revision		Revision as of 23:12, 17 November 2012
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	==Motivation==		==Motivation==
-	Motivation behind designing this shutter is speed, accuracy and variability (activation-time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right (this affects the force measurement) and make our feedback program run. To center the tether we need to turn the laser intensity (trap) on/off quickly for various time intervals. To do this we used to use AOM (acoustooptic module), because it’s extremely quick (nano second on/off time). But AOM has some inherent oscillation problem which makes it use as a switch, unsuccessful. So I needed ~~some thing~~ else (a shutter) which can replace this AOM function.	+	Motivation behind designing this shutter is speed, accuracy and variability (activation-time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right (this affects the force measurement) and make our feedback program run. To center the tether we need to turn the laser intensity (trap) on/off quickly for various time intervals. To do this we used to use AOM (acoustooptic module), because it’s extremely quick (nano second on/off time). But AOM has some inherent oscillation problem which makes it use as a switch, unsuccessful. So I needed something else, (a shutter) which can replace this AOM function.

-	This shutter does it exact~~. It~~ is fast (activation-time) with an opening time of 4 and closing time of 2 μsec. The shutter runs on a +5 volts voltage. It moves to an on-position with an active voltage (controlled by the toggle foot switch) working against a ~~restoring~~-spring and remains on when the voltage is applied and turns to off when the voltage is removed. This gives a freedom of choice for the ~~time~~ shutter is active ~~and~~ very simple electronics ~~controls~~ the speed (activation time)	+	This shutter does it exact and it is fast (activation-time) with an opening time of 4 and closing time of 2 μsec. The shutter runs on a +5 volts voltage. It moves to an on-position with an active voltage (controlled by the toggle foot switch) working against a restore-spring and remains on when the voltage is applied and turns to off when the voltage is removed. This gives a freedom of choice for the duration shutter is active with very simple electronics used to control the speed (activation time.)

-	In design the laser passes through an aperture~~, and~~ the only moving part ~~is the~~ cylinder. No gears, and no electronics in the ~~actual shutter, makes this~~ design very stable and accurate, even under the heat produced by ~~the~~ laser beam.	+	In the design the laser passes through an aperture on the only moving part a cylinder. No gears and no electronics in the design make it very simple, stable and accurate, even under the heat produced by a laser beam. The shutter needs no special power supply and can be run on a cell phone charge with an output of roughly 300mA/5V.
-	~~This~~ shutter needs no special power supply~~, it~~ can be run ~~through~~ a cell phone charge with an output of roughly 300mA/5V.	+
-	Cost and construction time is also important. With this design, a shutter can be prepared under $40 with 10 hours of construction time (10 x 25 (hourly wage of a technician)=$250+40=$290)~~. Still~~ better than many commercially available shutter systems with same performance.	+	Cost and construction time is also important. With this design, a shutter can be prepared under $40 with 10 hours of construction time (10 x 25 (hourly wage of a technician) =$250+40=$290), still better than many commercially available shutter systems with same performance.

	== Design & Construction==		== Design & Construction==

Pranav Rathi: /* Motivation */

Pranav Rathi — Sat, 17 Nov 2012 19:04:41 GMT

Motivation

←Older revision		Revision as of 19:04, 17 November 2012
Line 4:		Line 4:
	Motivation behind designing this shutter is speed, accuracy and variability (activation-time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right (this affects the force measurement) and make our feedback program run. To center the tether we need to turn the laser intensity (trap) on/off quickly for various time intervals. To do this we used to use AOM (acoustooptic module), because it’s extremely quick (nano second on/off time). But AOM has some inherent oscillation problem which makes it use as a switch, unsuccessful. So I needed some thing else (a shutter) which can replace this AOM function.		Motivation behind designing this shutter is speed, accuracy and variability (activation-time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right (this affects the force measurement) and make our feedback program run. To center the tether we need to turn the laser intensity (trap) on/off quickly for various time intervals. To do this we used to use AOM (acoustooptic module), because it’s extremely quick (nano second on/off time). But AOM has some inherent oscillation problem which makes it use as a switch, unsuccessful. So I needed some thing else (a shutter) which can replace this AOM function.

-	This shutter does it exact. It is fast (activation time) with an opening time of 4 and closing time of 2 μsec. The shutter runs on a +5 volts voltage. It moves to on-position with an active voltage (controlled by the toggle foot switch) working against a restoring-spring~~, it~~ remains on when the voltage is applied and turns to off when the voltage is removed. This gives a freedom of choice for the time shutter is active and very simple electronics controls the speed (activation time)	+	This shutter does it exact. It is fast (activation-time) with an opening time of 4 and closing time of 2 μsec. The shutter runs on a +5 volts voltage. It moves to an on-position with an active voltage (controlled by the toggle foot switch) working against a restoring-spring and remains on when the voltage is applied and turns to off when the voltage is removed. This gives a freedom of choice for the time shutter is active and very simple electronics controls the speed (activation time)

	In design the laser passes through an aperture, and the only moving part is the cylinder. No gears, and no electronics in the actual shutter, makes this design very stable and accurate, even under the heat produced by the laser beam.		In design the laser passes through an aperture, and the only moving part is the cylinder. No gears, and no electronics in the actual shutter, makes this design very stable and accurate, even under the heat produced by the laser beam.

Pranav Rathi: /* Motivation */

Pranav Rathi — Sat, 17 Nov 2012 19:02:24 GMT

Motivation

←Older revision		Revision as of 19:02, 17 November 2012
Line 2:		Line 2:

	==Motivation==		==Motivation==
-	Motivation behind designing ~~the~~ shutter is speed, accuracy and variability (time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right (~~because~~ this affects the force measurement) and make our feedback program run. To center the tether we need to turn the laser intensity (trap) on/off quickly for various time intervals. To do this we used to use AOM (acoustooptic module), because it’s extremely quick (nano second on/off time). But AOM has some inherent oscillation problem which makes it use as a switch, unsuccessful. So I needed some-thing which can replace this AOM function.	+	Motivation behind designing this shutter is speed, accuracy and variability (activation-time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right (this affects the force measurement) and make our feedback program run. To center the tether we need to turn the laser intensity (trap) on/off quickly for various time intervals. To do this we used to use AOM (acoustooptic module), because it’s extremely quick (nano second on/off time). But AOM has some inherent oscillation problem which makes it use as a switch, unsuccessful. So I needed some thing else (a shutter) which can replace this AOM function.

	This shutter does it exact. It is fast (activation time) with an opening time of 4 and closing time of 2 μsec. The shutter runs on a +5 volts voltage. It moves to on-position with an active voltage (controlled by the toggle foot switch) working against a restoring-spring, it remains on when the voltage is applied and turns to off when the voltage is removed. This gives a freedom of choice for the time shutter is active and very simple electronics controls the speed (activation time)		This shutter does it exact. It is fast (activation time) with an opening time of 4 and closing time of 2 μsec. The shutter runs on a +5 volts voltage. It moves to on-position with an active voltage (controlled by the toggle foot switch) working against a restoring-spring, it remains on when the voltage is applied and turns to off when the voltage is removed. This gives a freedom of choice for the time shutter is active and very simple electronics controls the speed (activation time)

Pranav Rathi: /* Motivation */

Pranav Rathi — Sat, 17 Nov 2012 18:53:17 GMT

Motivation

←Older revision		Revision as of 18:53, 17 November 2012
Line 2:		Line 2:

	==Motivation==		==Motivation==
-	Motivation behind designing the shutter is speed, accuracy and variability (time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right(because this affects the force measurement)and make our ~~feed-back~~ program run. To center the tether we need to turn the laser intensity on/off quickly for ~~variable~~ time intervals. To do this we used to use AOM, because it’s extremely quick (~~nsec~~) ~~and variable~~. So I needed some-thing which can replace this AOM function.	+	Motivation behind designing the shutter is speed, accuracy and variability (time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right (because this affects the force measurement) and make our feedback program run. To center the tether we need to turn the laser intensity (trap) on/off quickly for various time intervals. To do this we used to use AOM (acoustooptic module), because it’s extremely quick (nano second on/off time). But AOM has some inherent oscillation problem which makes it use as a switch, unsuccessful. So I needed some-thing which can replace this AOM function.
-	This shutter does it exact. It is fast with opening time of 4 and closing time 2 μsec. ~~Since the~~ shutter runs on/with ~~the~~ active voltage (controlled by the toggle foot switch), it remains ~~active with~~ the ~~applied~~ voltage~~, with the freedom~~ to ~~chose any active time~~. ~~The speed~~ of the shutter ~~can also be controlled.~~	+
		+	This shutter does it exact. It is fast (activation time) with an opening time of 4 and closing time of 2 μsec. The shutter runs on a +5 volts voltage. It moves to on-position with an active voltage (controlled by the toggle foot switch) working against a restoring-spring, it remains on when the voltage is applied and turns to off when the voltage is removed. This gives a freedom of choice for the time shutter is active and very simple electronics controls the speed (activation time)
		+
	In design the laser passes through an aperture, and the only moving part is the cylinder. No gears, and no electronics in the actual shutter, makes this design very stable and accurate, even under the heat produced by the laser beam.		In design the laser passes through an aperture, and the only moving part is the cylinder. No gears, and no electronics in the actual shutter, makes this design very stable and accurate, even under the heat produced by the laser beam.
	This shutter needs no special power supply, it can be run through a cell phone charge with an output of roughly 300mA/5V.		This shutter needs no special power supply, it can be run through a cell phone charge with an output of roughly 300mA/5V.

Pranav Rathi at 18:35, 17 November 2012

Pranav Rathi — Sat, 17 Nov 2012 18:35:42 GMT

←Older revision		Revision as of 18:35, 17 November 2012
Line 1:		Line 1:
-		+	https://lh4.googleusercontent.com/-4t9t2lciTB4/UKfY1P8IfeI/AAAAAAAAB4g/BCTJwMN6JNA/s640/Laser%2520enclosure%2520AOM2.jpg

	==Motivation==		==Motivation==

Pranav Rathi: /* Comments */

Pranav Rathi — Thu, 15 Nov 2012 20:33:20 GMT

Comments

←Older revision		Revision as of 20:33, 15 November 2012
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	[[Category:Construction of Optical Tweezers and devices]]		[[Category:Construction of Optical Tweezers and devices]]
-	~~[[Category:Optical Tweezer]]~~

Pranav Rathi at 23:43, 15 August 2011

Pranav Rathi — Mon, 15 Aug 2011 23:43:15 GMT

←Older revision		Revision as of 23:43, 15 August 2011
Line 1:		Line 1:
-	~~The full detail is coming soon.~~	+
		+
	==Motivation==		==Motivation==
	Motivation behind designing the shutter is speed, accuracy and variability (time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right(because this affects the force measurement)and make our feed-back program run. To center the tether we need to turn the laser intensity on/off quickly for variable time intervals. To do this we used to use AOM, because it’s extremely quick (nsec) and variable. So I needed some-thing which can replace this AOM function.		Motivation behind designing the shutter is speed, accuracy and variability (time). In our optical tweezers we need to center the trap over the tethered bead, to get the geometry right(because this affects the force measurement)and make our feed-back program run. To center the tether we need to turn the laser intensity on/off quickly for variable time intervals. To do this we used to use AOM, because it’s extremely quick (nsec) and variable. So I needed some-thing which can replace this AOM function.

Pranav Rathi: /* Comments */

Pranav Rathi — Mon, 15 Aug 2011 23:42:44 GMT

Comments

←Older revision		Revision as of 23:42, 15 August 2011
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	== Comments==		== Comments==
-	<div align="center"><html><div style="width:~~280px~~" id="__ss_8859065"><strong style="display:block;margin:12px 0 4px"><a href="http://www.slideshare.net/pranavrathi/motor-shutter-buildup" title="Motor shutter buildup">Motor shutter buildup</a></strong><object id="__sse8859065" width="~~280~~" height="~~280~~"><param name="movie" value="http://static.slidesharecdn.com/swf/ssplayer2.swf?doc=motorshutterbuildup-110815183358-phpapp02&stripped_title=motor-shutter-buildup&userName=pranavrathi" /><param name="allowFullScreen" value="true"/><param name="allowScriptAccess" value="always"/><embed name="__sse8859065" src="http://static.slidesharecdn.com/swf/ssplayer2.swf?doc=motorshutterbuildup-110815183358-phpapp02&stripped_title=motor-shutter-buildup&userName=pranavrathi" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="355"></embed></object><div style="padding:5px 0 12px">View more <a href="http://www.slideshare.net/">presentations</a> from <a href="http://www.slideshare.net/pranavrathi">pranavrathi</a>.</div></div></html></div>	+	<div align="center"><html><div style="width:600px" id="__ss_8859065"><strong style="display:block;margin:12px 0 4px"><a href="http://www.slideshare.net/pranavrathi/motor-shutter-buildup" title="Motor shutter buildup">Motor shutter buildup</a></strong><object id="__sse8859065" width="600" height="300"><param name="movie" value="http://static.slidesharecdn.com/swf/ssplayer2.swf?doc=motorshutterbuildup-110815183358-phpapp02&stripped_title=motor-shutter-buildup&userName=pranavrathi" /><param name="allowFullScreen" value="true"/><param name="allowScriptAccess" value="always"/><embed name="__sse8859065" src="http://static.slidesharecdn.com/swf/ssplayer2.swf?doc=motorshutterbuildup-110815183358-phpapp02&stripped_title=motor-shutter-buildup&userName=pranavrathi" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="355"></embed></object><div style="padding:5px 0 12px">View more <a href="http://www.slideshare.net/">presentations</a> from <a href="http://www.slideshare.net/pranavrathi">pranavrathi</a>.</div></div></html></div>

	[[Image:Shutter2.JPG\|left\|thumb\|400x280px\|Full Shutter System]]		[[Image:Shutter2.JPG\|left\|thumb\|400x280px\|Full Shutter System]]