# Wien displacement law

« Back to Glossary Index

[2.13.6] An expression representing, in a functional form, the spectral radiance of a blackbody as a function of the wavelength and the temperature.

$L_{\lambda }=dI_{\lambda}/dA' = c_{1L}\left (\lambda \right )^{-5} \cdot f\left ( \lambda T \right )$

or

$L_{\lambda } T^{-5}=c_{1L}(\lambda T)^{-5} \cdot f(\lambda T)$

$f\left ( \lambda T \right )= e^{-(c_{2}/\lambda T)}$

The two principal corollaries of this law are:

$\lambda _{m} T = b$

$L _{m}/ T^{5} = b'$

These show how the maximum spectral radiance Lm and the wavelength λm at which it occurs are related to the absolute temperature T.

Note: The currently recommended value of b is 2.8978 x 10-3 m•K, or 2.8978 x 10-1 cm•K. From the Planck radiation law, and with the use of the values of b, c1, and c2as given in that definition, b’ is found to be:

$4.0956 \cdot 10^{-14} \left ( W/cm^{2}\cdot sr\cdot \mu m\cdot K^{5} \right )$
« Back to Definitions Index

### EP Zoom Platinum Sponsor - $20,000 What’s in it for you? • Sponsor 5 Students/Emerging Professionals and the EP Day presentation platform • Visibility and awareness before breakout rooms and throughout the event • Opportunity to present a live or prerecorded personal closing message (15 seconds-1 minute duration) • Shout-outs throughout the event • Recognition as an EP Program Sponsor on all event communication • Recognition on the IES Annual Conference homepage • Recognition on the IES Annual Conference Emerging Professional homepage ### EP Sponsorship Opportunities Sponsor students and emerging professionals to attend the virtual Annual Conference event or the in-person Street & Area Lighting Conference. Student and EP recipients selected by Emerging Professional Committee. ### EP Breakout Room Sponsor -$8,000

What do you get?

•    Sponsor breakout room for live engagement and networking during EP Day
•    Opportunity to present a live or prerecorded personal welcome message (15 seconds-1 minute duration)
•    Visibility and awareness at the start of the schedule
•    Personalized zoom backgrounds for moderators
•    Recognition as an EP Program Sponsor on all event communication
•    Recognition on the IES Annual Conference homepage
•    Recognition on the IES Annual Conference Emerging Professional homepage
•    Opportunity to provide personalized swag to attendees and moderators

### EP Game Sponsor - $5,000 What are the benefits? • Sponsor live interactive game session(s) during EP Day • Ability to use your personal game hosting platform for the game session (IES can provide platform if needed) • Be a Game Co-Host • Opportunity to provide personalized swag or selection of IES publications as prize options ### 1 X Event Sponsor -$5,000

What’s in it for you?

•    Visibility and awareness before breakout rooms and throughout the event – graphic image of logo
•    Opportunity to submit a prerecorded personal opening/closing message (15 seconds-1 minute duration)
•    Shout-outs throughout the event
•    Recognition on the Leadership Forum homepage

### 6 X Breakout Room Sponsor - $1,000 – (1 for each of 6 Breakout Rooms) What do you get? • Visibility and awareness at the start of the schedule – [verbal announcement/thank you] • Personalized Zoom background for moderators – [moderators must use if provided by sponsor] • Recognition as a Leadership Forum Sponsor on all event communication • Recognition on the Leadership Forum homepage ### 3 X Leadership Forum Kahoot Game Sponsor -$500

What are the benefits?

•    Sponsor live interactive Kahoot game session(s) during LF Day
•    Be a Game Co-Host (optional)
•    Recognition on the Leadership Forum homepage

### 1x Gold Sponsor- $25,000 • Recognition as a Gold Sponsor in a fourth (1/4) page placement for 2 months in LD+A magazine • Recognition as Gold sponsor on event app and all event communication, excluding Registration and Daily Digest communications • Full registration for two (2) to the Annual Conference • Company logo and hyperlink placed on exhibitor page within event app ### 2x Keynote Sponsor-$10,000

•    2-3 minute Opening
•    Introduce keynote speaker
•    Company logo and hyperlink placed on exhibitor page within event app

### 5x Virtual Break Sponsor - $6,000 • Provided graphic visible during break duration • Recognition as Virtual Break sponsor on event app and all event communications, excluding Registration and Daily Digest communications • Full Registration for one (1) to the Annual Conference ### 1x Opening Session Sponsor-$5,000

•    90-second video prior to session start
•    Company logo and hyperlink placed on exhibitor page within event app

### 1x Closing Session Sponsor- $5,000 • 90-second video prior to session start • Company logo and hyperlink placed on exhibitor page within event app ### 1x Society Update Sponsor -$5,000

•    Recognition as Society Update sponsor throughout web
•    Recognition as Society Update sponsor on event app and all event communication, excluding Registration and Daily Digest communications
•    Full registration for one (1) to attend the 2021 Annual Conference
•    90-second video prior to session start

### 1x Registration Sponsor - $5,000 • Visibility as sole sponsor on the registration page and in all registration focused communications • Company logo and hyperlink placed on exhibitor page within event app ### 1x Daily Digest Sponsor -$5,000

•    Visibility as sole sponsor in all Daily Digest focused communications
•    Recognition on event webpage and communications as Daily Digest Sponsor

### 10x Event App Exhibitor Page Sponsor - \$1,000

•    Company logo and hyperlink placed on exhibitor page within event app