Optics
Optics
is simply put as the scientific study of sight and light. The ways employed in producing images are through the camera & projector and the human eye.
The simple lens camera is made up of a convex lens(in complex cameras, this is replaced by a system of lenses), a diaphragm, a shutter, a film and a film spool.
The projector is made up of the small but powerful light source that illuminates the non-luminous transparent object, the condenser which is made up of two plano convex lenses which collects the light to evenly illuminate the film, the slide carrier which is the framework in which the slide is placed upside down, so that it will appear erect on the screen. The projection lens which is placed in front of the slide to give a magnified, real and inverted image of the slide, but, because of this, the slide is placed upside down so that the image formed on the screen is in an erect position. Lastly, the screen, usually white, receives the image which is the right way up if the object is inserted upside down into the slide carrier.
The principle of the slide projector is used in cine-projectors, photographic enlargers and other numerous devices.
The human eye is a biological organ applied by Humans for vision, the optical system of the eye consists of the cornea, lens, aqueous humour and vitreous humour which works together to produce vision.
Two terms used in association to the eye are accommodation and binocular vision.
Accommodation is simply the ability to alter the focal length of the eyes' lens(convex) in order to form clear images of objects at different distances from the retina.
Binocular is the overlapping of the two images formed by the pair of eyes which makes us to see things in relief and gives us an impression of solidity and depth. However, the only way binocular vision is possible is if the fields of the two eyes overlap which is not possible in some birds due to the positioning of their eyes.
There is also another term called PERSISTENCE OF VISION which is the phenomenon that describes when an image formed on the retina leaves a sensation of vision for a short but definite amount of time even after the light is removed.
NORMAL VISION AND THE DEFECTS OF VISION
The NEAR POINT and FAR POINT of the human eyes are simply the nearest and farthest point from the retina from which objects can be conspicuously seen.
The near point for a normal human eye is about 25cm while the far point is i Note that the part of the eye responsible for adjusting the focal length of the eyes' lens is the CILIARY MUSCLES.
DEFECTS OF THE HUMAN EYE
I would mention some of the defects of the human eye which are long sightedness(hypermetropia),
and short sightedness(myopia).
Both short sightedness and long sightedness arise when the eye lens is unable to accommodate effectively.
Long sightedness is the ability of the eye to be able to see far objects but not being able to see near objects. This can be corrected by using a converging lens to focus the image on the retina(in long sightedness, the image from near objects is formed behind the retina,so,the converging lens focuses d image on d retina)
Short sightedness is the ability of the eye to be able to see near objects but not being able to see far objects, this is corrected by concave lenses (in short sightedness, the image from far objects is formed in front of the retina, so, the diverging lens focuses the image on the retina).
SIMILARITIES AND DIFFERENCES BETWEEN THE HUMAN EYE AND THE CAMERA
SIMILARITIES
1. The pupil in the eye serves the same purpose as the aperture of the camera.
2. The iris in the eye serves the same function as the diaphragm in the camera which is to control the amount of light entering the device/organ.
3. Both the eye and camera have converging lenses to focus rays from an external object.
4. In the camera is a light-tight box painted black inside and the human eye is impregnated with black pigment inside it.
5. Both the camera and the human eye have light-sensitive material on which the rays are focused. In the eye, it's the retina, in the camera, it's the photosensitive film.
DIFFERENCES
1. The eye can have defects of vision while the camera can not.
2. The camera is a mechanical device while the human eye is a biological organ, which brings about several lots of other differences.
3. The human's eye's lens and retina have a fixed distance between each other while the distance between the lens and the film of the camera is variable.
4. The human eye can alter its lens' focal length (Accommodation) while the focal length of the lens of a camera is fixed.
MICROSCOPES & TELESCOPES
A microscope is an instrument used to magnify objects while the telescope is also a microscope, just a more advanced one.
A simple microscope is simply a converging lens and the object to be viewed is placed between the optical centre of the lens and the principal focus,the lens is then adjusted until a clear image is seen at near point (25cm for a normal human eye). The image gotten from this is magnified, virtual and erect.
We also have the compound microscope, astronomical telescope, Galilean telescope and the prism binoculars.
The prism binoculars are a pair of astronomical telescopes(commonly called BINOCULARS being used to view distant objects by the pair of human eyes.
Each astronomical telescope is fitted with two right-angled isosceles prisms whose function is to re-invert the image formed by the objective lens and give an erect image to the eyepiece which also magnifies the image.
Thus, the prism binoculars give an erect & magnified image to the viewer.
{In telescopes where the lenses are two,eye piece . at is nearer to the object is called the objective lens,while the lens nearer to the eye is called the eye piece
The prism binoculars, due to the fact that they are in pairs, have an extra advantage of bringing the rays from two telescopes inwards to fit the distance apart of the two eyes i.e. The distance apart from the images formed by the pair of binoculars is equal to the distance between the pair of eyes of an average human being.
*_This is as far as we go on Optics, for further explanation on unclear terms, send a Direct Message to any of the admins, also make sure to do some personal research on your own as it is rudimentary and essential for the student to do some more research outside of class-knowledge.
Have a most nice day.
©2018 Physics-helper
is simply put as the scientific study of sight and light. The ways employed in producing images are through the camera & projector and the human eye.
The simple lens camera is made up of a convex lens(in complex cameras, this is replaced by a system of lenses), a diaphragm, a shutter, a film and a film spool.
The projector is made up of the small but powerful light source that illuminates the non-luminous transparent object, the condenser which is made up of two plano convex lenses which collects the light to evenly illuminate the film, the slide carrier which is the framework in which the slide is placed upside down, so that it will appear erect on the screen. The projection lens which is placed in front of the slide to give a magnified, real and inverted image of the slide, but, because of this, the slide is placed upside down so that the image formed on the screen is in an erect position. Lastly, the screen, usually white, receives the image which is the right way up if the object is inserted upside down into the slide carrier.
The principle of the slide projector is used in cine-projectors, photographic enlargers and other numerous devices.
The human eye is a biological organ applied by Humans for vision, the optical system of the eye consists of the cornea, lens, aqueous humour and vitreous humour which works together to produce vision.
Two terms used in association to the eye are accommodation and binocular vision.
Accommodation is simply the ability to alter the focal length of the eyes' lens(convex) in order to form clear images of objects at different distances from the retina.
Binocular is the overlapping of the two images formed by the pair of eyes which makes us to see things in relief and gives us an impression of solidity and depth. However, the only way binocular vision is possible is if the fields of the two eyes overlap which is not possible in some birds due to the positioning of their eyes.
There is also another term called PERSISTENCE OF VISION which is the phenomenon that describes when an image formed on the retina leaves a sensation of vision for a short but definite amount of time even after the light is removed.
NORMAL VISION AND THE DEFECTS OF VISION
The NEAR POINT and FAR POINT of the human eyes are simply the nearest and farthest point from the retina from which objects can be conspicuously seen.
The near point for a normal human eye is about 25cm while the far point is i Note that the part of the eye responsible for adjusting the focal length of the eyes' lens is the CILIARY MUSCLES.
DEFECTS OF THE HUMAN EYE
I would mention some of the defects of the human eye which are long sightedness(hypermetropia),
and short sightedness(myopia).
Both short sightedness and long sightedness arise when the eye lens is unable to accommodate effectively.
Long sightedness is the ability of the eye to be able to see far objects but not being able to see near objects. This can be corrected by using a converging lens to focus the image on the retina(in long sightedness, the image from near objects is formed behind the retina,so,the converging lens focuses d image on d retina)
Short sightedness is the ability of the eye to be able to see near objects but not being able to see far objects, this is corrected by concave lenses (in short sightedness, the image from far objects is formed in front of the retina, so, the diverging lens focuses the image on the retina).
SIMILARITIES AND DIFFERENCES BETWEEN THE HUMAN EYE AND THE CAMERA
SIMILARITIES
1. The pupil in the eye serves the same purpose as the aperture of the camera.
2. The iris in the eye serves the same function as the diaphragm in the camera which is to control the amount of light entering the device/organ.
3. Both the eye and camera have converging lenses to focus rays from an external object.
4. In the camera is a light-tight box painted black inside and the human eye is impregnated with black pigment inside it.
5. Both the camera and the human eye have light-sensitive material on which the rays are focused. In the eye, it's the retina, in the camera, it's the photosensitive film.
DIFFERENCES
1. The eye can have defects of vision while the camera can not.
2. The camera is a mechanical device while the human eye is a biological organ, which brings about several lots of other differences.
3. The human's eye's lens and retina have a fixed distance between each other while the distance between the lens and the film of the camera is variable.
4. The human eye can alter its lens' focal length (Accommodation) while the focal length of the lens of a camera is fixed.
MICROSCOPES & TELESCOPES
A microscope is an instrument used to magnify objects while the telescope is also a microscope, just a more advanced one.
A simple microscope is simply a converging lens and the object to be viewed is placed between the optical centre of the lens and the principal focus,the lens is then adjusted until a clear image is seen at near point (25cm for a normal human eye). The image gotten from this is magnified, virtual and erect.
We also have the compound microscope, astronomical telescope, Galilean telescope and the prism binoculars.
The prism binoculars are a pair of astronomical telescopes(commonly called BINOCULARS being used to view distant objects by the pair of human eyes.
Each astronomical telescope is fitted with two right-angled isosceles prisms whose function is to re-invert the image formed by the objective lens and give an erect image to the eyepiece which also magnifies the image.
Thus, the prism binoculars give an erect & magnified image to the viewer.
{In telescopes where the lenses are two,eye piece . at is nearer to the object is called the objective lens,while the lens nearer to the eye is called the eye piece
The prism binoculars, due to the fact that they are in pairs, have an extra advantage of bringing the rays from two telescopes inwards to fit the distance apart of the two eyes i.e. The distance apart from the images formed by the pair of binoculars is equal to the distance between the pair of eyes of an average human being.
*_This is as far as we go on Optics, for further explanation on unclear terms, send a Direct Message to any of the admins, also make sure to do some personal research on your own as it is rudimentary and essential for the student to do some more research outside of class-knowledge.
Have a most nice day.
©2018 Physics-helper
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