Optique Comment voit-on les choses?

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1 Optique Comment voit-on les choses?
Somewhere between a quarter and a third of humans neocortex is devoted to vision. We are very good at recognizing and distinguishing fairly subtle patterns, quickly decoding printed pages, for example, or distinguish between trees based on the pattern of their leaves or bark. We accomplish this by having a very flexible and powerful visual system.

2 Qu’est-ce que l’optique géométrique?
L’étude des rayons lumineux L’étude du comportement de la lumière quand elle frappe des objets Music to the deaf is like colour to the blind. How we see thing depends on how our sense perceive things in the physical world and how our brain interprets what our sense perceive. In order to understand sight we first have to understand what we call light in the physical world. We also have to understand how our eyes and brain work. This course will concentrate mostly on how light behaves in the physical world. The study of this is called Optics.

3 Je vous présente monsieur Oeil
Je vous présente monsieur Oeil. Je l’utiliserai souvent pour simplifier les dessins utilisés en optique.

4 Le bout de la flamme d’une chandelle émet de la lumière dans toutes les directions. Mais on voit seulement la lumière qui atteint notre oeil Demonstrate that we can’t see the light that does not enter our eyes by using a laser pointer. Direct the laser beam across the classroom, Make the beam visible by misting water over the beam with hand held atomizer. As the tiny drops of water fall through the beam they scatter light into the students eyes. This is called the Tyndall Effect. The Tyndall Effect is caused by reflection of light by very small particles in suspension in a transparent medium. It is often seen from the dust in the air when sunlight comes in through a window, or comes down through holes in clouds.

5 On ne voit pas tous les rayons de lumière.
Demonstrate that we can’t see the light that does not enter our eyes by using a laser pointer. Direct the laser beam across the classroom, Make the beam visible by misting water over the beam with hand held atomizer. As the tiny drops of water fall through the beam they scatter light into the students eyes. This is called the Tyndall Effect. The Tyndall Effect is caused by reflection of light by very small particles in suspension in a transparent medium. It is often seen from the dust in the air when sunlight comes in through a window, or comes down through holes in clouds.

6 Par exemple, on ne voit pas la lumière qui est dirigée dans une autre direction à moins que quelque chose la fasse réfléchir à notre oeil. Demonstrate that we can’t see the light that does not enter our eyes by using a laser pointer. Direct the laser beam across the classroom, Make the beam visible by misting water over the beam with hand held atomizer. As the tiny drops of water fall through the beam they scatter light into the students eyes. This is called the Tyndall Effect. The Tyndall Effect is caused by reflection of light by very small particles in suspension in a transparent medium. It is often seen from the dust in the air when sunlight comes in through a window, or comes down through holes in clouds.

7 Dans ce module, nous allons ignorer la lumière qui ne vient pas à notre oeil.
Demonstrate that we can’t see the light that does not enter our eyes by using a laser pointer. Direct the laser beam across the classroom, Make the beam visible by misting water over the beam with hand held atomizer. As the tiny drops of water fall through the beam they scatter light into the students eyes. This is called the Tyndall Effect. The Tyndall Effect is caused by reflection of light by very small particles in suspension in a transparent medium. It is often seen from the dust in the air when sunlight comes in through a window, or comes down through holes in clouds.

8 Le trajet que suis la lumière est nommé un RAYON
Le trajet que suis la lumière est nommé un RAYON. Des dessins qui démontrent le trajet et la direction de la lumière d’un objet à l’oeil se nomme des DIAGRAMMES À RAYONS

9 Quelles sont les propriétés de la lumière?
-Elle voyage en ligne droite -Elle voyage à très grande vitesse -Elle est un type d’onde électromagnétique Rectilinear Propagation

10 Peux-tu voir les pieds de monsieur Oeil?
Rectilinear Propagation

11 Puisque la lumière voyage en ligne droite, aucun rayon de lumière ne peut voyager des pieds de monsieur Oeil à tes yeux. Rectilinear Propagation

12 Rectilinear Propagation

13 Newton fut le premier à remarquer que lorsque la lumière blanche traverse un prisme elle forme des couleurs. La raison est que le prisme ralentit la vitesse de la lumière. Sir Isaac Newton’s full name with title is easy to remember because of his initials (i.e. SIN)

14 Lorsque la lumière blanche est divisée, on voit les couleurs de l’arc en ciel.
Very good full spectrum from overhead projector – Fisher Science Education - Diffraction Grating 6x5 Roll for overhead projector S Science First No.:PS-08-B Encourage students to make up their own mnemonic for remembering the order of rainbow colours. Let them know “A mnemonic is just a way to remember simple lists” To show students a very good full spectrum see Note the Capital letters denote the Additive Primary colours. More on this later in “Seeing Colour.ppt” Isaac Newton named the colors of the spectrum we use today. At first he only identified 5 colours (red, yellow, green, blue, violet) He changed this to seven colors out of a mistaken belief, derived from the ancient Greeks. They believed there was a connection between the colors, the musical notes, the known objects in the solar system, and the days of the week. Newton therefore added Orange and Indigo to make up 7 names for the main colours of he spectrum i.e. ROYGBIV, Red, Orange, Yellow, Green, Blue, Indigo, Violet

15 Newton a remarqué que chaque couleur individuelle ne peut pas être séparée d’avantage. Les couleurs pures, ont chacune leur propre fréquence et longueur d’onde.

16 Nos oreilles ne peuvent pas entendre certaines fréquences que les chiens peuvent entendrent. Tout comme nos yeux ne peuvent pas voir certaines couleurs de la lumière. Radiometer and hot iron E3.2 identify and label the visible and invisible regions of the electromagnetic spectrum

17 Par exemple, tu ne peux pas voir si un fer à repasser est chaud ou non
Par exemple, tu ne peux pas voir si un fer à repasser est chaud ou non. Nos yeux ne peuvent pas voir les ondes émissent par le fer, mais nos mains peuvent le ressentir. Les ondes émissent par le fer à repasser se nomment les ondes Infra Rouges. Radiometer and hot iron E3.2 identify and label the visible and invisible regions of the electromagnetic spectrum The facts some snakes can see Infra Red Radiation gives them the advantage of being able to better perceive warm blooded prey in the dark

18 La lumière visible est une toute petite partie du grand SPECTRE ÉLECTROMAGNÉTIQUE.
E3.2 identify and label the visible and invisible regions of the electromagnetic spectrum

19 Mnémonique pour le SPECTRE DE LUMIÈRE VISIBLE
Mnémonique pour t’aider à te souvenir du SPECTRE ÉLECTROMAGNÉTIQUE Radio Ondes Micro Ondes Infra Rouge Lumière Visible Ultra Violet Rayons X Rayons Gamma Rachel's Mother Is Visiting Uncle Xavier's Garden . Mnémonique pour le SPECTRE DE LUMIÈRE VISIBLE E3.2 identify and label the visible and invisible regions of the electromagnetic spectrum Rouge Orange Jaune Vert Bleu Indigo Violet Risk Of Juice Vomit Before Initial Voyage

20 Une diode électroluminscente (DEL) Un laser La fluorescence
La lumière visible peut être produite par plusieurs différentes sources. Par exemple: La bioluminescence La phosphorescence La triboluminescence Une diode électroluminscente (DEL) Un laser La fluorescence La décharge électrique La chimiluminescence L’incandescence. E3.1 describe and explain various types of light emissions (e.g., chemiluminescence, bioluminescence, incandescence, fluorescence, phosphorescence, triboluminescence; from an electric discharge or light-emitting diode [LED]) A handout is supplied