dealing with the eye. llike light enters the eye, light focuses on the retnina, then what?
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How you spell? What are ojects?
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See an eye doctor.\n\nIt might be something on the lens, or it might be something on the retina. Or it might be some completely different thing.
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The retina in the back of the eye is a thin and transparent sensitive film.\n\nIt contains two types of receptor cells, rods and cones.\n\nCones handle day and color vision.\n\nRods are responsible for night vision. They are concentrated more at the sides of\nthe eye’s back wall. Therefore, objects are best seen at the sides, or ‘corners’ of our eyes, where rods are there.\n\nRods  are super sensitive than cones.  That is they respond to very small power of light.\n\nBut they take some 30 to 40 minutes to reach their maximum effectiveness.\n\nThey do not react to colors but react to the brightness.
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The eyes. If there isn't any life in them, it's usually a waste of time to try to go further.
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cornea the surface of which is covered with a layer of cells called epithelium\n\nokay I may have misunderstood the question, I thought the question was what structures BEFORE the retina, not HOW the retina works, hence my answer.
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The pupil is a circular opening that opens and closes according to how much light it's being exposed to. If too much light is let in you can't see anything at all. I suspect that cats have different shaped pupils because their eyes are designed to be able to see in almost ZERO light.
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Just imagine that a ray of light bounces in a droplet of water, and that broken wavelength bounces out another side of the water droplet, divided into it's color components.\n\nThe only colored light that reaches your eye, is the water droplets that are uniquely pointing in your direction. Hence, the bow affect, since those droplets are uniquely pointing that color to your eyes. \n\nFunny way of thinking about it, but another person standing 1/2 mile away from you is seeing different water droplets producing the same rainbow affect. Even someone standing 10 feet way is seeing the affect of different water droplets.
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You are in a 10-foot room with a light in the center.  The photons leave the light, zoom to the wall in 5 nanoseconds, reflect off the wall, and (some of them) zoom into your eye 5 nanoseconds later,  where your brain perceives them about 300 millisconds later.\n\nYou turn off the light.  Generally, the light will cool and stop emitting photons within, say, 100 milliseconds.  But suppose it is a specially-constructed light, and it turns off in 10 picoseconds.  The last photons stream to the wall in 5 nanoseconds, reflect, and hit your eyes 5 nanoseconds later.   Some of the photons that miss your eye may reflect off the walls several times, but there is a 20 to 80% chance of their being absorbed by the paint on the wall each time they reflect.  The brightness in the room therefore decreases a factor of about 2 every 10 nanoseconds.  Within 100 nanoseconds, the number of photons in the room has decreased a factor of about 1000, and it becomes dark.
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Brain regulates the pupils.  If pupils dont respond to light, it is possible she'd have brain damage.
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The photoreceptor cells in the deepest (surprisingly!) layer of the retina encode the light image into electrical signals.  There is NO form of fibre optic light pipe.  The signal is purely electrical, not light, from the first cell in the system onwards.\n(When I say purely electrical, I mean not light, ie electrical and chemical neurotranmitter/receptor, of course.)\n\nNeural synapses occur through a sequence of several cells before the pattern of neural impulses reaches the optic nerve. Oddly, the light has to pass through these neurons in order to reach the photoreceptors.\n\nI understand these synapses are arranged so as to identify and encode contrasting edges and lines, providing initial processing of the image within the eye. \n\nI claim no more than the most elementary knowledge, so hopefully further answers will detail what processing exactly is performed before the optic nerve takes the messages to the temporal cortex and tectum.\n\nPerhaps more chance of this if not under "Engineering".
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On the back inner surface of each eye is a unique tissue called the "retina." All images entering the eye fall on the retina - just as images entering a camera fall on the film. The human retina contains two types of light-sensing cells: \n\nThe "cones" are specialized cells which fill the central part of the retina. The cones sense and discriminate colors. They also see most clearly, giving us our sharp, clear, fully colored, daytime vision. The cones, however, see only ahead but not to the sides (no peripheral vision), and they do not sense very dim light. The cones function with and complement the functions of other retinal cells called the "rods." \nThe "rods" are specialized cells which fill the peripheral or the off-center portions of the retina. The rods see only in black, white and gray. They do not discriminate colors. The rods give us side or peripheral vision, in bright daylight, in very dim light, and in mixed lighting conditions such as being on a dark road at night with bright oncoming headlights shining into one’s eyes. In very dim light, with no bright lights visible, a person is probably seeing with his rods, only. This is confirmed if everything appears in black, white and gray – without colors. In a dim-light environment, with one or two bright pinpoint lights, the person sees with both the cones (for the bright light) and the rods (for the dim light). Unfortunately, prolonged viewing of a bright light in a dim field causes the wide pupils to close to smaller sizes and may also desensitize the rods - temporarily reducing the person's ability to see in dim light. Thus, nighttime drivers want oncoming cars to lower their headlight beams, to prevent their being blinded. Once the bright light is gone, the pupils open up again and the rod cells resensitize, thus restoring good night vision. Most aircraft and some autos use red lights to illuminate the panel instruments because this color does not contract the pupils or overload the rods. \nCategory 1 – Blurred Vision in Dim Light … with sharp vision in moderate to bright light. These people see clearly in daylight but with blurred vision at night or in semi-darkness. They usually do not complain of "too little" ambient light and they do not complain of glare. People with this problem are the most numerous of all the people with night vision impairments and are often in their 40's or 50's. MOST CAN BE HELPED EFFECTIVELY with a pair of prescription glasses prescribed especially for night driving or outdoors night vision at distance.\n\nMOSTLY AFFECTED are people whose ages range from the mid-40's to the mid-50's who are starting to become presbyopic due to aging. Typically, the person has some slight refractive error that does not affect visual acuity in bright light … but does reduce the person’s visual acuity in dim light. This results in the “blurred night vision” complaints. In most cases, both eyes are affected equally. People whose two eyes react differently should refer to additional information below.\n\nTHE CAUSE of "impaired night vision" in these cases is, most often, variation in the "depth-of-focus" of each eye with exposure to bright or dim light - and the resulting closing or opening of the eye's iris. In bright light, with the iris closed and the pupil of the eye small or even “pinpoint,” there is great depth-of-focus so that objects near and far remain in sharp focus. This conceals minor refractive errors such as common myopia (nearsightedness) and/or astigmatism (non-uniform corneal curvature distortions). A person attempts to drive at night in an area that has little or no ambient artificial lighting. The pupils become large as the iris opens. More light comes into each eye so that there is no complaint of being "night blind." However, with the large pupils, the depth-of-focus is reduced and the distant scene or road, sidewa
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What's with those copycat answers, with even the spelling and punctuation errors copied?\n\nThe cones of the retina are in the center and provide color perception. The rods are distributed around the center and are more sensitive to light than the cones, but are not sensitive to color. In low light, you will see better with the more sensitive rods, which are off-center in the retina.
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There are several reasons for blurry vision, the most common of which is called refractive error.  The eye is a complex system that takes light and focuses it on special cells in the back of the eye (in the retina).  These cells take the light information and send it back to the brain, which tells you what it is that you're seeing.  \n\nIf your eye focuses light in front of the retina (instead of directly on it), you get blurry vision that's called myopia or nearsightedness.  If your eye focuses light behind the retina, you get blurry vision that's called hyperopia or farsightedness.  It's all related to the optical power and length of the eye.\n\nGlasses and contact lenses work by refocusing light directly onto the retina, giving you clear vision again.  You should also know that there are many eye diseases that can cause blurry vision that is not correctable with glasses or contact lenses.
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good grief - there is a lot of 'part' knowledge here...\n\nyou need to break this down and talk about the different parts of what the original question was asking.\n\nif it was 'see', the explanation would be the same as for hearing by the way. (it would be easier to explain about seeing)\n\nhere goes...\n\ninside your ear you have these little hairs (cillia) that are a certain distance apart. when a sound wave enters the ear the wavelength of this wave will stimulate hairs at both its high energy points (its troughs or peaks, you choose, not important) your brain knows the distance of the hairs and so can interprut this wave distance between two lots of hairs being stimulated. thats how you get the frequency (number of wavelengths in a second) of sound in your ear. the volume (loudness) depends on how vigourously the hairs are moved by the sound wave. (thats why you can go deaf listening to loud music - you kill those little hairs if too loud). \n\nnotice i said sound!\n\nyour question is about electromagnetic waves. radio waves and visible light (green) waves are both of the same stuff (light energy - some we can see and some we cannot). the organ for detecting this energy is the eye. inside the eye, the retina (back of the eye) has special cells called rods and cones for detecting different wavelengths (i believe this is what your engineer was on about). each of these cells has a specific chemical for detecting a certain wavelength. lets pick on one.\n\nthe red light cone has a protein inside that has a special part that can move to a slightly higher energy form (a more awkward position for the proten so it wants to get back to where it was before - think of bending a ruler... the more you bend it, the more it wants to get back to where it was... so the higher the energy it has) when red light is shone on that protein (inside the eye) it provides enough energy to move this extra part of the protein (called an apoprotein portion is anyone wants to know) to a higher energy state and this is enough to induce (make happen) a signal being sent to the brain that says 'red light detected' and we see red light.\n\na similar thing happens to green light.\n\nin physics, when we talk of waves whether in music or lihgth or nanometers, if you have something of the same wavelength then it is detected as the same.\n\nif you have something of a different wavelngth then it is detect as different ( or in the case of the eye.. or even the ear, not detected at all, unless your are green, red or blue light)\n\nbut if you have a wavelength that is say  x2 bigger, of x3 or x6 or x2000 times bigger exactly, with no extra and no bits needed.. it has to be exact. then these also will be detected.. A BIT. we call thesse harmonics. this is a word that belongs to music.\n\never notice the way a piano has all those notes (only 8 notes and yet so many keys..?) these eight notes are repeated but in higher registers/keys, but they are still the same note.... a higher harmonic. all these wavelenths are doubled or trippled or what ever.\n\nso, because there will be a harmonic of green light in the radiowave part of the spectrum... it can theoretically be detected. so you could theoretically detect green light (with the eye) and radiowaves (theoretically with the eye)... but never with the ear :-)\n\nhappy days - now lets look at information theory! why do we always lose information and yet still maintain the integroty of the message? at what point is the message lost?
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Glasses, contact lenses or Lasik. You did not cause the eye problem, you were born that way. You cannot make your eyes near or far sighted by reading in the dark, using the computer too much, etc
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Go to the eye doctor right now --do not delay.  You are experiencing the start of a retina tear. It will detach next. Leave it alone and blindness will be your companion shortly.
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http://en.wikipedia.org/wiki/Eyesight