Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Virtual Reality > Chapter 4 > Flashcards

Chapter 4 Flashcards

1
Q

three descciptions of light

A

photons waves rays

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

photons

A

tiny particles of energy moving through space at high speeds - helpful when consdiering amount of light received by snesor or receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

waves

A

ripples thorugh space, wavelength is the distance between peaks - helpful when consdiering spectrum of colosr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

rays

A

traces motion of single hypothetical photon and perpendicular to wavefronts - helpful when explaining lenses and defining concept of visibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

wave spreading

A

desnity (photons per second per area) same in all directions but decrease as light source becomes more distant as well as curvature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

parallel wavefronts

A

if waves were to propagat infinitely far away then they would completely flatten

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

at a finite distance from a point light source…

A

rays of light diverge, impossible to make them converge without help of lenses and mirror

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

three behaviors as light strikes surface of material

A

transmission, absorption, reflection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

transmission

A

energy travel through material and exit other sit (glass) light rays are slowed and bend/ if translucent that is not tranpasrent, rays scatter into various directions before exiting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

absorption

A

energy is absorbed by the material as lightbecome trapped

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

reflection

A

light deflected from surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

specular reflection

A

exit anygle is equal to entry engle on perfectly smooth surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

diffuse reflection

A

reflected rays are scattered in arbitrary directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

ways energy is divided between cases

A

angle of approach, wavelength and differences between two adjacent materials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

coherent versus jumbled light

A

light sources do not emit coherent light (wavefronts perfectly aligned in time and space with exception of laser) / light bulbs and sun emit jumble that have various wavelengths and no peaks aligned

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

spectral color

A

perceive with coherent light source fixed at one wavelength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

700 - 100 nm

A

infrared no visible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

100 - 400 nm

A

ultraviolet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

perception of color

A

observe light relfected from ojbject around us / each surface has own distribution of wavelengths it reflects and fraction of light energy reflected back depend on ewavelength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

to perceive red as an object sruface what needs to happen

A

red wavelengths must be included in light source and surface must strongly relfect red wavelengths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

frequency

A

number of times per second wave peaks pass through fixed location

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

snells law

A

how much rays of light bend when entering or extigin a transparent material
n1 sintheta1 = n2 sintheta 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

refractive index

A

n = c/s where is is speed of light in medium, n is how long it takes to traverse medium through vacuum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

prism

A

larger refractive index would cause greater bending inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
focal point
parallel horizontal rays of light converge to a point on the other side of the lens - convergence
26
focal depth or length
distance from lens center
27
1/s1 + 1/s2 = 1/f
focal length is f, light source placed at distance s1
28
if light source is too close to the lens
outgoing rays might be diverging so much that lens cannot force them to convergeand real image not formed
29
magnification and vr
virtual image appears when looking into lens --several lenses placed in succession
30
concave
parallel rays forced to diverge rather than converge
31
diopter
D = 1/f , larger the D greater the converging power smaller the greater divergence
32
aberrations
imperfections that dgrade images formed by lenses
33
chromatic aberration
separates focuse image based on color
34
how to reduce chromatic abertation
combine conves and concave lenses of different materials so they converge
35
spherical aberration
caused by rays further away from lens center being refractoed more than rays near the center
36
monochromatic aberration
independent of light wavelength - spherical aberration / incoming parallel rays focused at varying dpeths not concentrated at single point
37
petzvel surface
image might focus on to curved surface the petzvel rather than image plane with spherical aberration
38
aspehric lens
non spherical surfaces to eliminate spherical aberration
39
optical distortions
distorted at the perhipheral - stretch or compress image
40
two types of optical disotritons
barrel distorition and pincushion distortion
41
fish eyed lens
vide field of view where distoriton is strongerand is a type of barrel distortion
42
astigmatism
lens aberration that occurs for incoming rays not perpedicualr to the lens/ cornea has excessively elliptical shape rather than symmetruy
43
coma
aberration where image magnification vaires dramatically as the rays are far from perpedicaulr to the lens
44
lens flare
aberration where rays from birght light scatter through lens and show circular patters
45
retina as related to focal plane
replaced by this spherically curved surface
46
cornea and lens
two convex lenses
47
accommodation
lens changes diopter to accommodate closer distance
48
presbyiopia
as you age little or no accommodation ability remains - 50 yrs
49
hyperopia or farsightness
opitcal system doesnt have enoguth optical power to converge parallel rays to retina
50
fixing hyperopia
place convex lens with poistive diopter in fron of the eye
51
myopia or near sighteness
when eyes have too much optical power
52
how to fix myopia
concave lens with negative diopter is placed in front of eye to reduce optical power
53
correct astigmatsm
non simple lenses
54
vr headset screen and lenses
place it 10cm away and can focus , optical power increase dby convex lens - place at distance of ofcal length (x2 = -f meaning s1 = infinity resulting in screening apearing as enromous virtual image ininitye far away
55
focusing knob
varies distance between lens and screen - adjusts opitcal power so rays between lens and cornea arent parallel and can be made to converge or diverge for hyperopia or myopia/ but if each eye needs different diopter than need knob for each eye and cant correct for astigmaism
56
interpupillary distance
distance between human eye centers - 55-75mm
57
camera obscura
allows light to pass through pinholle onto surface containing real image
58
two technologies for electronically capturing image using a sensory with digital camers
charge coupled device array and cmos active pixel image sensor
59
how do these digital technnologies work
record amount of light hitting each pixel location along image which directly procues a capture image
60
what is the image in when cpatured on digital image
2d array of pixels, each having red green and blue 0-255
61
higher resolution camera
less photons per pixels because pixels are smaller
62
how to control amount of photons
shutter
63
shutter
blocks light, lopens for fixed interval of time and closes
64
low shutter speed
long interval, more light collected but moving objects might seem blurry and sensing elements could be saturated wtih too much lights
65
how cmos sensors work
sned image info sequentially line by line so coupled with rolling shutter
66
rolling shutter
sllows light to enter for each line just before info is snet and can get odd artifacts
67
how ccd snesors work
grab and send entire image at once resuling in global shutter
68
aperture lens
convex so multiple rays converge to same point on image plane genertating more photons per sensing elememnt / but focuses on objects on single dept while blurring others

Virtual Reality (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions