Skip to main content
Springer Nature Link
Log in

The Total Irradiance Monitor (TIM): Instrument Design

  • Published:
Save article
View saved research
Solar Physics Aims and scope Submit manuscript

Abstract

The Total Irradiance Monitor (TIM) instrument is designed to measure total solar irradiance with an absolute accuracy of 100 parts per million. Four electrical substitution radiometers behind precision apertures measure input radiant power while providing redundancy. Duty cycling the use of the radiometers tracks degradation of the nickel-phosphorous absorptive black radiometer interiors caused by solar exposure. Phase sensitive detection at the shutter frequency reduces noise and simplifies the estimate of the radiometer's equivalence ratio. An as-designed uncertainty budget estimates the instrument's accuracy goal. The TIM measurement equation defines the conversion from measured signal to solar irradiance.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Subscribe and save

Springer+
from $39.99 /Month
  • Starting from 10 chapters or articles per month
  • Access and download chapters and articles from more than 300k books and 2,500 journals
  • Cancel anytime
View plans

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Explore related subjects

Discover the latest articles, books and news in related subjects, suggested using machine learning.

References

  • Foukal, P.: 2003, EOS Trans. AGU 84, 22, 205.

    Google Scholar 

  • Gundlach, J. H., Adelberger, E. G., Heckel, B. R., Swanson, and H. E.: 1996, Phys. Rev. D, 54, R1256.

    Article  ADS  Google Scholar 

  • Kopp, G., Heuerman, K., and Lawrence, G.: 2005, Solar Phys., this volume.

  • Kopp, G., Lawrence, G., and Rottman, G.: 2003, SPIE Proc. 5171, 14.

    ADS  Google Scholar 

  • Lawrence, G. M., Rottman, G., Harder, J., and Wood, T.: 2000, Metrologia 37, 407.

    Article  ADS  Google Scholar 

  • Lawrence, G. M., Kopp, G., Rottman, G., Harder, J., Woods, T., and Loui, H.: 2003, Metrologia 40, S78.

    Article  ADS  Google Scholar 

  • Lean, J., Beer, J., and Bradley, R.: 1995, Geophys. Res. Lett. 22, 3195.

    ADS  Google Scholar 

  • Pang, K. D. and Yau, K. K.: 2002, EOS Trans. AGU 83, 43, 489.

    Google Scholar 

  • Rax, B. G., Lee, C. I., and Johnston, A. H.: 1997, IEEE Trans. Nuclear Sci. 44, 1939.

    Article  ADS  Google Scholar 

  • Rice, J. P., Lorentz, S. R., and Jung, T. M.: 1999, in: 10th Conference on Atmospheric Radiation, 28 June–2 July, Madison, Wisconsin (Preprint volume).

  • Spreadbury, P. J.: 1991, IEEE Trans. Instrum. Meas. 40, 343.

    Article  Google Scholar 

  • Willson, R. C.: 1979, J. Appl. Opt. 18, 179.

    ADS  Google Scholar 

  • Willson, R. C., Gulkis, S., Janssen, M., Hudson, H. S., and Chapman, G. A.: 1981, Science 211, 700.

    ADS  Google Scholar 

  • Woods, T., Rottman, G., Harder, G., Lawrence, G., McClintock, B., Kopp, G. et al.: 2000, SPIE Proc. 4135, 192.

    ADS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, 80303

    Greg Kopp & George Lawrence

Authors
  1. Greg Kopp
    View author publications

    Search author on:PubMed Google Scholar

  2. George Lawrence
    View author publications

    Search author on:PubMed Google Scholar

Corresponding author

Correspondence to Greg Kopp.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kopp, G., Lawrence, G. The Total Irradiance Monitor (TIM): Instrument Design. Sol Phys 230, 91–109 (2005). https://doi.org/10.1007/s11207-005-7446-4

Download citation

  • Received:

  • Accepted:

  • Issue date:

  • DOI: https://doi.org/10.1007/s11207-005-7446-4

Keywords