1 / 15

# ECE-1466 Modern Optics Course Notes Part 6 - PowerPoint PPT Presentation

ECE-1466 Modern Optics Course Notes Part 6. Prof. Charles A. DiMarzio Northeastern University Spring 2002. Lecture Overview. Some Radiometry Terminology Equations Relating Radiometric Parameters Photometric Parameters Some Numbers A Little Bit of Scattering Theory

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about ' ECE-1466 Modern Optics Course Notes Part 6' - cyrah

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

### ECE-1466Modern OpticsCourse NotesPart 6

Prof. Charles A. DiMarzio

Northeastern University

Spring 2002

Chuck DiMarzio, Northeastern University

• Terminology

• Photometric Parameters

• Some Numbers

• A Little Bit of Scattering Theory

• Some Applications in Microscopy

Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University

M, Flux/Proj. Area

Notes: Spectral x=dx/dn or dx/dl: Add subscript n or w, divide units by Hz or mm.

F, Flux

Watts

Luminous Flux

Lumens

Watts/m2

Luminous Exitance

Lumens/m2=Lux

1 W is 683 L at 555 nm.

Watts/m2/sr

Luminance

Lumens/m2/sr

1 Lambert=

(1L/cm2/sr)/p

I, Flux/W

L,Flux/AW

Watts/sr

Luminous Intensity

Lumens/sr

E, Flux/Area Rcd.

Watts/m2

Illuminance

Lumens/m2=Lux

1 ftLambert= (1L/ft2/sr)/p

1mLambert= (1L/m2/sr)/p

1 Ft Candle=1L/ft2

1 Candela=1cd=1L/sr

Chuck DiMarzio, Northeastern University

1.8

This curve shows the relative sensitivity of the eye. To convert to photometric units from radiometric, multiply by 683 Lumens Per Watt

y

1

Photopic Sensitivity

0

400

500

600

700

800

Wavelength, nm

Chuck DiMarzio, Northeastern University

dA2

dA’

dA1

dW2

dW1

z

Chuck DiMarzio, Northeastern University

Our Example =

0.0037/p W/m2/sr

~ 0.001 W/m2/sr

at f/1

Half-Lux Camera

=

0.0044 W/m2/sr

Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University

10

10

m

/

2

5

10

0

10

-5

10

-10

10

l

M

-1

0

1

2

10

10

10

10

l

m

, Wavelength,

m

Black Body Equations (2)

10000

5000

2000

500

1000

T=300k

Chuck DiMarzio, Northeastern University

Data from The Science of Color, Crowell, 1953

3000

Exoatmospheric filename=m1695.m

Sea Level

2

5000 K Black Body Normalized to 1000 W/m

2500

2

6000 K Black Body Normalized to 1560 W/m

m

m

/

2

2000

1500

1000

l

E

500

0

0

200

400

600

800

1000

1200

1400

1600

1800

2000

l

, Wavelength, nm

Chuck DiMarzio, Northeastern University

• 3000 K

• 20 Lumens per Watt

• lpeak=1.22mm

• x = .4357y = .4032 z = .1610

• 3400 K note: (3400/3000)4=1.64)

• 34 Lumens per Watt note: 20X1.64=33

• lpeak=1.09mm

• x = .4112y = .3935 z = .1953

y

x

Chuck DiMarzio, Northeastern University

• Tungsten Filament

• Higher Temperature = Brighter, Whiter

• Requires Quartz Envelope

• Tungsten Evaporates More Rapidly

• Halogen Catalyst

• Prevents Tungsten Deposit on Hot Envelope

• Tungsten Redeposits on the Filament

• Evaporation and Redeposition Requires Thicker Filament

• Lower Resistance Requires Lower Voltage

Chuck DiMarzio, Northeastern University

1000000

Fluorescent

94 Lumens/Watt at 7000K

(Highest Efficiency

Black Body)

Hi Pressure

Na

Metal Halide

100000

Lo Pressure

Na

Incandescent

10000

Light Output, Lumens

Thanks to John Hilliar (NU MS ECE 1999) for finding lighting data from Joseph F. Hetherington at www.hetherington.com. 10 June 1998

1000

20.7 Lumens/Watt at 3000K

100

10000

1

10

100

1000

Power Input, Watts

0.142 W

• Fraction of Light in Filter Passband

• Given by Black-Body Equation

• Numerical Calculation is Easiest

100W

Black Body Spectral and Integrated Flux Density Rev 2.17

by Chuck DiMarzio, Northeastern University 1992,1993,1995, 1997

.49600 to .50400 micrometers, T = 3000.0 K

Maximum Spectral Radiant Exitance = .81762E+06 W/m^2/micron in band

Radiant Exitance in Band 6541.5 Watts/m^2

Wide Band Radiant Exitance .45925E+07 Watts/m^2

Fraction of total in band.14244E-02 Spectrum on bbsre.dat

****************************************************************************

Photocurrent per Area in Band 2669.5 Amps/m^2

.16663E+23 photons/sec/m^2

Average Responsivity .40808 Amps/Watt

.39257E-18 Joules/photon (in band)

...

Chuck DiMarzio, Northeastern University

• Mostly a Geometric Problem

• G describes non-uniformity

• Like Antenna Gain

Distance

=R

E = GP/(4pR2)

Power

=P

E = (1?)0.14 W/[4p(0.3)m2]

~ 0.12 W/m2

Comparable to a dark cloud

Chuck DiMarzio, Northeastern University