Why do we need a screen to see a real image whereas a virtual image can be seen without a screen?












3














We did a physics practical in which I couldn't see the image formed by the convex lens without the screen. But I can see the virtual image formed by the plane mirror without a screen.






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    Duplicate You do not need a screen to see a real image.
    – Farcher
    yesterday
















3














We did a physics practical in which I couldn't see the image formed by the convex lens without the screen. But I can see the virtual image formed by the plane mirror without a screen.






optics







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  • 2




    Duplicate You do not need a screen to see a real image.
    – Farcher
    yesterday














3












3








3







We did a physics practical in which I couldn't see the image formed by the convex lens without the screen. But I can see the virtual image formed by the plane mirror without a screen.






optics







share|cite|improve this question















We did a physics practical in which I couldn't see the image formed by the convex lens without the screen. But I can see the virtual image formed by the plane mirror without a screen.






optics




optics






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edited 18 hours ago









Peter Mortensen

1,92611323




1,92611323










asked yesterday









Monkyman

242




242








  • 2




    Duplicate You do not need a screen to see a real image.
    – Farcher
    yesterday














  • 2




    Duplicate You do not need a screen to see a real image.
    – Farcher
    yesterday








2




2




Duplicate You do not need a screen to see a real image.
– Farcher
yesterday




Duplicate You do not need a screen to see a real image.
– Farcher
yesterday










2 Answers
2






active

oldest

votes


















4














You can see real images without a screen. Just look through a converging lens. If what you see is upside-down, then you are seeing a real image.



You are only able to use a screen to show where a real image is because light rays physically converge to a point in space.



When you use a screen, the screen "sees" the real image just as if your eye was where the screen was$^*$. Then we see what is reflected from the screen.



For the plane mirror you are just seeing a reflection, just as if the "mirror image" of your world was placed behind where the mirror if located without the mirror actually being there. Seeing things in a mirror is essentially just like seeing things normally.




$^*$ This is neglecting the fact that your eye is also a lens, so in reality you don't want your eye to be exactly at the image.






share|cite|improve this answer























  • I had practical class in which I could not see the real image until I put a screen there
    – Monkyman
    yesterday






  • 1




    @Monkyman If you had put your eye where the screen was you would have seen the real image. Screens are used to reflect that real image to your eyes.
    – Aaron Stevens
    yesterday












  • but then for a virtual image on a plane mirror you need not put your eyes anywhere but you can still comfortably see the image . why is that so ? thanks for helping out
    – Monkyman
    yesterday










  • @Monkyman I have added more about the plane mirror
    – Aaron Stevens
    yesterday










  • but I still dont get how you have to place your eyes at the point of image formation for a real image to see the image and for a virtual image you can just stand anywhere and still see the image
    – Monkyman
    yesterday



















-1














This might help.
Try focussing the sun with a convex mirror on your hand. You can not merely see it. You can feel it. That is a real image.
You cannot catch a virtual image on a screen. You can catch a real image on a screen. (Just as you could do it on your hand.) It is a more convenient way to see a real image.
I my school physics lab, we would use pointed needles to determine the distances. We have to adjust the position of the image pin to avoid parallax. When the room was a bit dusty we could actually see the real inverted image of the object pin from the side.






share|cite|improve this answer

















  • 1




    Your first experience is poorly described and could be dangerous depending on how it is understood. Please clarify, prove that it's safe or remove it.
    – Eric Duminil
    19 hours ago










  • I fail to see what is so dangerous about using a convex lense to focus the sun into the skin. You would feel the heat and move the lense fast enough.
    – Dr S T Lakshmikumar
    1 hour ago











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2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









4














You can see real images without a screen. Just look through a converging lens. If what you see is upside-down, then you are seeing a real image.



You are only able to use a screen to show where a real image is because light rays physically converge to a point in space.



When you use a screen, the screen "sees" the real image just as if your eye was where the screen was$^*$. Then we see what is reflected from the screen.



For the plane mirror you are just seeing a reflection, just as if the "mirror image" of your world was placed behind where the mirror if located without the mirror actually being there. Seeing things in a mirror is essentially just like seeing things normally.




$^*$ This is neglecting the fact that your eye is also a lens, so in reality you don't want your eye to be exactly at the image.






share|cite|improve this answer























  • I had practical class in which I could not see the real image until I put a screen there
    – Monkyman
    yesterday






  • 1




    @Monkyman If you had put your eye where the screen was you would have seen the real image. Screens are used to reflect that real image to your eyes.
    – Aaron Stevens
    yesterday












  • but then for a virtual image on a plane mirror you need not put your eyes anywhere but you can still comfortably see the image . why is that so ? thanks for helping out
    – Monkyman
    yesterday










  • @Monkyman I have added more about the plane mirror
    – Aaron Stevens
    yesterday










  • but I still dont get how you have to place your eyes at the point of image formation for a real image to see the image and for a virtual image you can just stand anywhere and still see the image
    – Monkyman
    yesterday
















4














You can see real images without a screen. Just look through a converging lens. If what you see is upside-down, then you are seeing a real image.



You are only able to use a screen to show where a real image is because light rays physically converge to a point in space.



When you use a screen, the screen "sees" the real image just as if your eye was where the screen was$^*$. Then we see what is reflected from the screen.



For the plane mirror you are just seeing a reflection, just as if the "mirror image" of your world was placed behind where the mirror if located without the mirror actually being there. Seeing things in a mirror is essentially just like seeing things normally.




$^*$ This is neglecting the fact that your eye is also a lens, so in reality you don't want your eye to be exactly at the image.






share|cite|improve this answer























  • I had practical class in which I could not see the real image until I put a screen there
    – Monkyman
    yesterday






  • 1




    @Monkyman If you had put your eye where the screen was you would have seen the real image. Screens are used to reflect that real image to your eyes.
    – Aaron Stevens
    yesterday












  • but then for a virtual image on a plane mirror you need not put your eyes anywhere but you can still comfortably see the image . why is that so ? thanks for helping out
    – Monkyman
    yesterday










  • @Monkyman I have added more about the plane mirror
    – Aaron Stevens
    yesterday










  • but I still dont get how you have to place your eyes at the point of image formation for a real image to see the image and for a virtual image you can just stand anywhere and still see the image
    – Monkyman
    yesterday














4












4








4






You can see real images without a screen. Just look through a converging lens. If what you see is upside-down, then you are seeing a real image.



You are only able to use a screen to show where a real image is because light rays physically converge to a point in space.



When you use a screen, the screen "sees" the real image just as if your eye was where the screen was$^*$. Then we see what is reflected from the screen.



For the plane mirror you are just seeing a reflection, just as if the "mirror image" of your world was placed behind where the mirror if located without the mirror actually being there. Seeing things in a mirror is essentially just like seeing things normally.




$^*$ This is neglecting the fact that your eye is also a lens, so in reality you don't want your eye to be exactly at the image.






share|cite|improve this answer














You can see real images without a screen. Just look through a converging lens. If what you see is upside-down, then you are seeing a real image.



You are only able to use a screen to show where a real image is because light rays physically converge to a point in space.



When you use a screen, the screen "sees" the real image just as if your eye was where the screen was$^*$. Then we see what is reflected from the screen.



For the plane mirror you are just seeing a reflection, just as if the "mirror image" of your world was placed behind where the mirror if located without the mirror actually being there. Seeing things in a mirror is essentially just like seeing things normally.




$^*$ This is neglecting the fact that your eye is also a lens, so in reality you don't want your eye to be exactly at the image.







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited 15 mins ago

























answered yesterday









Aaron Stevens

9,07931640




9,07931640












  • I had practical class in which I could not see the real image until I put a screen there
    – Monkyman
    yesterday






  • 1




    @Monkyman If you had put your eye where the screen was you would have seen the real image. Screens are used to reflect that real image to your eyes.
    – Aaron Stevens
    yesterday












  • but then for a virtual image on a plane mirror you need not put your eyes anywhere but you can still comfortably see the image . why is that so ? thanks for helping out
    – Monkyman
    yesterday










  • @Monkyman I have added more about the plane mirror
    – Aaron Stevens
    yesterday










  • but I still dont get how you have to place your eyes at the point of image formation for a real image to see the image and for a virtual image you can just stand anywhere and still see the image
    – Monkyman
    yesterday


















  • I had practical class in which I could not see the real image until I put a screen there
    – Monkyman
    yesterday






  • 1




    @Monkyman If you had put your eye where the screen was you would have seen the real image. Screens are used to reflect that real image to your eyes.
    – Aaron Stevens
    yesterday












  • but then for a virtual image on a plane mirror you need not put your eyes anywhere but you can still comfortably see the image . why is that so ? thanks for helping out
    – Monkyman
    yesterday










  • @Monkyman I have added more about the plane mirror
    – Aaron Stevens
    yesterday










  • but I still dont get how you have to place your eyes at the point of image formation for a real image to see the image and for a virtual image you can just stand anywhere and still see the image
    – Monkyman
    yesterday
















I had practical class in which I could not see the real image until I put a screen there
– Monkyman
yesterday




I had practical class in which I could not see the real image until I put a screen there
– Monkyman
yesterday




1




1




@Monkyman If you had put your eye where the screen was you would have seen the real image. Screens are used to reflect that real image to your eyes.
– Aaron Stevens
yesterday






@Monkyman If you had put your eye where the screen was you would have seen the real image. Screens are used to reflect that real image to your eyes.
– Aaron Stevens
yesterday














but then for a virtual image on a plane mirror you need not put your eyes anywhere but you can still comfortably see the image . why is that so ? thanks for helping out
– Monkyman
yesterday




but then for a virtual image on a plane mirror you need not put your eyes anywhere but you can still comfortably see the image . why is that so ? thanks for helping out
– Monkyman
yesterday












@Monkyman I have added more about the plane mirror
– Aaron Stevens
yesterday




@Monkyman I have added more about the plane mirror
– Aaron Stevens
yesterday












but I still dont get how you have to place your eyes at the point of image formation for a real image to see the image and for a virtual image you can just stand anywhere and still see the image
– Monkyman
yesterday




but I still dont get how you have to place your eyes at the point of image formation for a real image to see the image and for a virtual image you can just stand anywhere and still see the image
– Monkyman
yesterday











-1














This might help.
Try focussing the sun with a convex mirror on your hand. You can not merely see it. You can feel it. That is a real image.
You cannot catch a virtual image on a screen. You can catch a real image on a screen. (Just as you could do it on your hand.) It is a more convenient way to see a real image.
I my school physics lab, we would use pointed needles to determine the distances. We have to adjust the position of the image pin to avoid parallax. When the room was a bit dusty we could actually see the real inverted image of the object pin from the side.






share|cite|improve this answer

















  • 1




    Your first experience is poorly described and could be dangerous depending on how it is understood. Please clarify, prove that it's safe or remove it.
    – Eric Duminil
    19 hours ago










  • I fail to see what is so dangerous about using a convex lense to focus the sun into the skin. You would feel the heat and move the lense fast enough.
    – Dr S T Lakshmikumar
    1 hour ago
















-1














This might help.
Try focussing the sun with a convex mirror on your hand. You can not merely see it. You can feel it. That is a real image.
You cannot catch a virtual image on a screen. You can catch a real image on a screen. (Just as you could do it on your hand.) It is a more convenient way to see a real image.
I my school physics lab, we would use pointed needles to determine the distances. We have to adjust the position of the image pin to avoid parallax. When the room was a bit dusty we could actually see the real inverted image of the object pin from the side.






share|cite|improve this answer

















  • 1




    Your first experience is poorly described and could be dangerous depending on how it is understood. Please clarify, prove that it's safe or remove it.
    – Eric Duminil
    19 hours ago










  • I fail to see what is so dangerous about using a convex lense to focus the sun into the skin. You would feel the heat and move the lense fast enough.
    – Dr S T Lakshmikumar
    1 hour ago














-1












-1








-1






This might help.
Try focussing the sun with a convex mirror on your hand. You can not merely see it. You can feel it. That is a real image.
You cannot catch a virtual image on a screen. You can catch a real image on a screen. (Just as you could do it on your hand.) It is a more convenient way to see a real image.
I my school physics lab, we would use pointed needles to determine the distances. We have to adjust the position of the image pin to avoid parallax. When the room was a bit dusty we could actually see the real inverted image of the object pin from the side.






share|cite|improve this answer












This might help.
Try focussing the sun with a convex mirror on your hand. You can not merely see it. You can feel it. That is a real image.
You cannot catch a virtual image on a screen. You can catch a real image on a screen. (Just as you could do it on your hand.) It is a more convenient way to see a real image.
I my school physics lab, we would use pointed needles to determine the distances. We have to adjust the position of the image pin to avoid parallax. When the room was a bit dusty we could actually see the real inverted image of the object pin from the side.







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered yesterday









Dr S T Lakshmikumar

292




292








  • 1




    Your first experience is poorly described and could be dangerous depending on how it is understood. Please clarify, prove that it's safe or remove it.
    – Eric Duminil
    19 hours ago










  • I fail to see what is so dangerous about using a convex lense to focus the sun into the skin. You would feel the heat and move the lense fast enough.
    – Dr S T Lakshmikumar
    1 hour ago














  • 1




    Your first experience is poorly described and could be dangerous depending on how it is understood. Please clarify, prove that it's safe or remove it.
    – Eric Duminil
    19 hours ago










  • I fail to see what is so dangerous about using a convex lense to focus the sun into the skin. You would feel the heat and move the lense fast enough.
    – Dr S T Lakshmikumar
    1 hour ago








1




1




Your first experience is poorly described and could be dangerous depending on how it is understood. Please clarify, prove that it's safe or remove it.
– Eric Duminil
19 hours ago




Your first experience is poorly described and could be dangerous depending on how it is understood. Please clarify, prove that it's safe or remove it.
– Eric Duminil
19 hours ago












I fail to see what is so dangerous about using a convex lense to focus the sun into the skin. You would feel the heat and move the lense fast enough.
– Dr S T Lakshmikumar
1 hour ago




I fail to see what is so dangerous about using a convex lense to focus the sun into the skin. You would feel the heat and move the lense fast enough.
– Dr S T Lakshmikumar
1 hour ago


















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