Slides captions:
optics
Ways to transfer influences
The transfer of matter from a source to a receiver. (hit the string) Measurement of the state of the medium between bodies (without transfer of matter). (place two strings side by side and sound waves from the first string, reaching the second, will cause it to sound)
corpuscular
Newton studied this theory. Light is a stream of particles coming from a source in all directions (substance transfer) Difficulties: Why do light beams intersect in space
wave
Huygens studied this theory. Light is waves propagating in a special hypothetical medium - ether, which fills all space and penetrates into all bodies. Difficulties: Rectilinear propagation and shadow formation
Corpuscular and wave theories of light
In the second half of the 19th century (Maxwell) - light was considered as a wave.
At the beginning of the 20th century, ideas about the nature of light changed. Light, when emitted and absorbed, behaves like a stream of particles
artificial
natural
stars
comet
sun
splinter
lamp
candle
bacteria on fish
bonfire
The phenomena of interference and diffraction could be explained by considering light as a wave
The phenomena of emission and absorption could be explained if light was considered a stream of particles
Light interference addition of light waves
Diffraction of light bending around small obstacles.
Light emission is the process of emitting and propagating energy in the form of waves and particles.
Absorption of light Reduction of the intensity of light emission
geometric optics
A branch of optics that studies the laws of light propagation in transparent media, the laws of light reflection from mirror surfaces, and the principles of imaging when light passes through optical systems.
Basic position of geometric optics
Light travels in a straight line
PHOTOMETRY (Greek photus - light and metrё - I measure)
Photometry
section of OPTICS in which they study how to measure light energy.
Photometry as a science is based on the developed theory of the light field
A light field is an area of space filled with light.
Part of the light flux, limited by a conical or cyclic surface, is called a light beam
Light beam. Light beam.
light beam the line along which the light beam propagates
A light beam is a stream of light energy
A light beam is the direction in which energy travels.
*
The angle of incidence is equal to the angle of reflection. The incident beam, the reflected beam, and the perpendicular restored at the point of incidence of the beam lie in the same plane.
The Law of Light Reflection The angle of incidence is the angle between the incident ray and the normal to the reflecting surface. At the point of fall.
α
β
*
Huygens principle
*
Huygens principle
Each point, to which the disturbance has reached, itself becomes a source of secondary spherical waves. The wave surface is the envelope of secondary waves.
model
*
BUT
A1
AT
FROM
C1
D
N
M
Angles B and C are straight
Angle DAC = αAngle ADB = β
Angles with mutually perpendicular sides
Side AD-common
α = β
AB=CD
R=AB=CD=vt
α
β
DAC=ADB
α
β
IN 1
D1
*
*
Light refraction
*
Law of refraction
The ratio of the sine of the angle of incidence of the beam to the sine of the angle of refraction is a constant value for these two media. The incident, refracted beam and the perpendicular restored at the point of incidence of the beam lie in the same plane.
α
β
*
Huygens principle
Each point, to which the disturbance has reached, itself becomes a source of secondary spherical waves. The wave surface is the envelope of secondary waves.
model
*
BUT
A1
AT
IN 1
FROM
C1
D
N
M
D1
υ1
υ2
Consider ∆ADC and ∆ADB
Angle DAC = αAngle ADB = β
α
β
α
β
*
BUT
A1
AT
IN 1
FROM
C1
D
N
M
D1
υ1
υ2
α
β
Consider ∆ADC and ∆ADB
Angle DAC = αAngle ADB = β
(Angles with mutually perpendicular sides)
*
When a beam passes from a less dense medium to a denser medium
α
β
υ2
υ1
When a beam passes from a denser medium to a less dense
α
β
υ2
υ1
*
The physical meaning of the refractive index
α
β
n2, υ2
n1, υ1
*
Substance
n
Substance
n
Acetone
1.36
Organic glass
1.50
Diamond
2.42
Sulphuric acid
1.43
Benzene
1.50
Ruby
1.76
Rock salt
1.54
Turpentine
1.47
Water
1.33
Mica
1.58
Quartz
1.54
Alcohol
1.36
Glycerol
1.47
Glass (regular)
1.48 - 1.53
Ice
1.31
Glass (optical)
1.47 - 2.04
Castor oil
1.48
Ether
1.35
*
*
Total internal reflection
α0
βmax
βmax = 900
sin 900 = 1
*
Total internal reflection
*
Total internal reflection
*
Total internal reflection
*
Total internal reflection
*
1 slide
2 slide
Optics is the study of the nature of light, light phenomena and the interaction of light with matter. And almost all of its history is the history of the search for an answer: what is light?
3 slide
The history of the development of optics One of the first theories of light - the theory of visual rays - was put forward by the Greek philosopher Plato around 400 BC. e. This theory assumed that rays come from the eye, which, meeting with objects, illuminate them and create the appearance of the surrounding world. The views of Plato were supported by many scientists of antiquity and, in particular, Euclid (3rd century BC), based on the theory of visual rays, founded the doctrine of the rectilinear propagation of light, established the law of reflection.
4 slide
In the same years, the following facts were discovered: rectilinearity of light propagation; the phenomenon of light reflection and the law of reflection; the phenomenon of light refraction; focusing action of a concave mirror.
5 slide
The most interesting work on optics that has come down to us from the Middle Ages is the work of the Arab scientist Alhazen. He studied the reflection of light from mirrors, the phenomenon of refraction and the passage of light through lenses. Alhazen was the first to suggest that light has a finite propagation velocity. This hypothesis was a major step in understanding the nature of light.
6 slide
The main provisions of optics: Light is emitted, propagated and absorbed in discrete portions - quanta. A quantum of light - a photon carries an energy proportional to the frequency of the wave with which it is described by the electromagnetic theory E=h . A photon has mass (m=hv/c), momentum m=hv/c and angular momentum (_=h/2П).
7 slide
A photon, as a particle, exists only in motion, the speed of which is the speed of light propagation in a given medium. For all interactions in which a photon participates, the general laws of conservation of energy and momentum are valid. An electron in an atom can only be in some discrete stable stationary states. Being in stationary states, the atom does not radiate energy. During the transition from one stationary state to another, an atom emits (absorbs) a photon with a frequency v=E –E /h, (where E1 and E2 are the energies of the initial and final states).
8 slide
The eye as an optical system. The organ of human vision is the eyes, which in many respects represent a very perfect optical system.
9 slide
In general, the human eye is a spherical body with a diameter of about 2.5 cm, which is called the eyeball. The opaque and strong outer shell of the eye is called the sclera, and its transparent and more convex front part is called the cornea.
10 slide
C onclusion: The field of phenomena studied by physical optics is very extensive. Optical phenomena are closely related to phenomena studied in other branches of physics, and optical research methods are among the most subtle and accurate. Therefore, it is not surprising that for a long time optics played a leading role in very many fundamental research and the development of basic physical views. Suffice it to say that both main physical theories of the last century - the theory of relativity and the theory of quantum - originated and developed largely on the basis of optical research. The invention of lasers opened up vast new possibilities not only in optics, but also in its applications in various branches of science and technology.
Presentation on the topic "Optics" in physics in powerpoint format. This presentation for schoolchildren tells what theories of light existed, what is a luminous flux, a light beam, a light beam, light intensity, illumination. Presentation author: teacher Kachanova Irina Alekseevna.
Fragments from the presentation
Optics
The branch of physics that studies light phenomena is called optics (from the Greek "opticos" visual), and light phenomena are usually called optical.
Answer the questions:
- What are the transmission methods? Give examples.
- What theories on the study of light were put forward and how did they differ?
- What is called geometric optics?
- Fundamentals of geometric optics.
Ways to transfer influences
- The transfer of matter from a source to a receiver. (hit the string)
- Measurement of the state of the medium between bodies (without the transfer of matter). (place two strings side by side and sound waves from the first string, reaching the second, will cause it to sound)
Corpuscular and wave theories of light
corpuscular
- Newton studied this theory
- Light is a stream of particles going from a source in all directions (substance transfer)
- Difficulties:
- Why do light beams intersect in space
wave
- Huygens studied this theory
- Light is waves propagating in a special hypothetical medium - ether, which fills all space and penetrates into all bodies
- Difficulties:
- Rectilinear propagation and shadow casting
- In the second half of the 19th century, light was considered as a wave.
At the beginning of the 20th century, ideas about the nature of the set changed.
Light, when emitted and absorbed, behaves like a stream of particles
geometric optics
- A branch of optics that studies the laws of light propagation in transparent media, the laws of light reflection from mirror surfaces, and the principles of imaging when light passes through optical systems.
- The basic position of geometric optics - Light propagates in a straight line
Photometry
- PHOTOMETRY (Greek photós - light and metréo - I measure) a section of OPTICS that studies how to measure light energy.
- Photometry as a science is based on the developed theory of the light field
- light field- an area of space filled with light.
Light flow
The quantity measured by the amount of energy emitted by a light source per unit of time is called luminous flux
Light beam. Light beam.
- Part of the light flux, limited by a conical or cyclic surface, is called a light beam
- light beam the line along which the light beam propagates
- light beam is the flow of light energy
- light beam is the direction in which energy travels
Solid angle
the part of space bounded by some conical surface is called a solid angle.
The power of light. illumination
- The quantity measured by the amount of energy emitted by a light source per unit time within a solid angle is called by the power of light
- The value measured by the amount of light energy supplied per unit surface of the body in one second is called illumination
Illumination standards
To preserve vision and create normal working conditions, it is necessary to maintain the most favorable illumination.
Optimum illumination standards (lx)
- Workplace for fine work........ 200
- Reading...................100
- In the workplace for rough work.......30
- In the corridors and on the stairs............15
- Passages in the premises .............. 10
- On the streets and squares .............. 4
- In courtyards and porches............. 2
Very specific requirements are imposed on the illumination of the operating field in surgery. The light falling on the surgical field should create a uniform optimal illumination with a minimum thermal effect, not tire the doctor and not create shadows. For this purpose, lamps of a special design, the so-called shadowless lamps, are used.
slide 1
Teaching aid for students
Teacher of the Blagoveshchensk Medical College Kachanova Irina Alekseevna
slide 2
Optics Light sources Photometry Luminous flux Light beam. Light beam. The power of light. Illumination. Illumination standards
slide 3
The branch of physics that studies light phenomena is called optics (from the Greek "opticos" visual), and light phenomena are usually called optical.
Answer the questions: What ways of transferring influences exist? Give examples. What theories on the study of light were put forward and how did they differ? What is called geometric optics? Fundamentals of geometric optics.
Work with the textbook Physics 11kl., G.Ya. Myakishev, B.B. Bukhantsev pp. 168 - 170.
slide 4
Ways to transfer influences
The transfer of matter from a source to a receiver. (hit the string) Measurement of the state of the medium between bodies (without the transfer of matter). (place two strings side by side and sound waves from the first string, reaching the second, will cause it to sound)
slide 5
corpuscular
Newton studied this theory. Light is a stream of particles coming from a source in all directions (substance transfer) Difficulties: Why do light beams intersect in space
wave
Huygens studied this theory. Light is waves propagating in a special hypothetical medium - ether, which fills all space and penetrates into all bodies. Difficulties: Rectilinear propagation and the formation of shadows
Corpuscular and wave theories of light
In the second half of the 19th century, light was considered as a wave.
At the beginning of the 20th century, ideas about the nature of the set changed. Light, when emitted and absorbed, behaves like a stream of particles
slide 6
The phenomena of interference and diffraction could be explained by considering light as a wave
The phenomena of emission and absorption could be explained if light was considered a stream of particles
Light interference addition of light waves
Diffraction of light around small obstacles.
Light emission is the process of emitting and propagating energy in the form of waves and particles.
Absorption of light Reduction of the intensity of light emission
Slide 7
geometric optics
A branch of optics that studies the laws of light propagation in transparent media, the laws of light reflection from mirror surfaces, and the principles of imaging when light passes through optical systems.
Basic position of geometric optics
Light travels in a straight line
Slide 8
Artificial Natural Stars Comet Sun Splinter Lamp Light Sources Candle Bacteria On Fish Bonfire True
Slide 9
PHOTOMETRY (Greek photós - light and metréo - I measure)
Photometry
section of OPTICS in which they study how to measure light energy.
Photometry as a science is based on the developed theory of the light field
A light field is an area of space filled with light.
Slide 10
The quantity measured by the amount of energy emitted by a light source per unit of time is called luminous flux.
Light flow
time [s, min, hours]
amount of energy [J]
luminous flux [lm] (lumen)
slide 11
Part of the light flux, limited by a conical or cyclic surface, is called a light beam
Light beam. Light beam.
light beam the line along which the light beam propagates
A light beam is a stream of light energy
A light beam is the direction in which energy travels.
slide 12
the part of space bounded by some conical surface is called a solid angle.
Solid angle
The solid angle is measured by part of the spherical surface ABCDEF
Sphere area [m2] Sphere radius [m]
solid angle [sr] (steradian)
slide 13
The value measured by the amount of energy that is emitted by a light source per unit time inside a solid angle is called the luminous intensity
The power of light. illumination
luminous intensity [cd] (candela)
The value measured by the amount of light energy supplied per unit surface of the body in one second is called illumination.
surface area [m2]
illumination [lx] (lux)
Slide 14
To preserve vision and create normal working conditions, it is necessary to maintain the most favorable illumination. Optimum illumination rates (lx) At the workplace for fine work .......... 200 For reading .................. 100 At the workplace for rough work. ......30 In corridors and on stairs.............15 Passages in rooms...............10 In streets and squares.... ......... 4 In the yards and entrances............. 2 Very specific requirements are placed on the illumination of the surgical field in surgery. The light falling on the surgical field should create a uniform optimal illumination with a minimum thermal effect, not tire the doctor and not create shadows. For this purpose, lamps of a special design, the so-called shadowless lamps, are used.
Illumination standards
slide 15
literature
en.wikipedia.org › Wikipedia 5terka.com › Geometric optics images.yandex.ru › Yandex. Pictures http://www.bymath.net › All elementary mathematics
