THE LANDSAT DATA CONTINUITY MISSION
OPERATIONAL LAND IMAGER (OLI) SENSOR
1 2 2 2 2 2
Brian L. Markham , Edward J. Knight , Brent Canova , Eric Donley , Geir Kvaran , Kenton Lee ,
Julia A . Barsi \ Jeffrey A. Pedelty 1 , Philip W Dabney 1 and James R . Irons 1
^ASA/GSFC, Greenbelt, MD 20771; 2 Ball Aerospace & Technology Corp., Boulder, CO 80301;
3 SSAI/GSFC, Greenbelt, MD 20771
The Landsat Data Continuity Mission (LDCM) is being developed by NASA and USGS and is currently planned
for launch in January 2013 . Once on-orbit and checked out, it will be operated by USGS and officially named
Landsat-8. Two sensors will be on LDCM: the Operational Land Imager (OLI), which has been built and
delivered by Ball Aerospace & Technology Corp (BATC) and the Thermal Infrared Sensor (TIRS), currently
being built and tested at Goddard Space Flight Center (GSFC) with a planned delivery of Winter 2012. The OLI
covers the Visible, Near-IR (NIR) and Short-Wave Infrared (SWIR) parts of the spectrum; TIRS covers the
Thermal Infrared (TIR). This paper discusses only the OLI instrument and its pre-launch characterization; a
companion paper covers TIRS.
2. INSTRUMENT DESCRIPTION
The OLI is an all-reflective pushbroom radiometer that images a 185 km swath like the whiskbroom TM and
ETM+ instruments (Figure 1,2). The OLI has 7 spectral bands (Table 1) that are similar to the reflective bands
on the ETM+, though refined in bandwidth and location. In addition, it has a band centered at 443 nm that is
intended to provide additional information about coastal regions and the atmosphere, and a band centered at 1373
nm for detection of cirrus clouds. As per the ETM+, all spectral bands, with the exception of the panchromatic
band are 30m IFOV; the pan band is 15 m. The dynamic range of OLI is set that it will not saturate for non-
specular targets across all solar zenith angles observed on orbit. OLI data are transmitted at 12-bit radiometric
The OLI is designed to achieve 5% uncertainty in radiance calibration and 3% uncertainty in reflectance
calibration. To assist in maintaining this calibration, two full aperture Spectralon™ solar diffusers are part of the
instrument as well as internal lamps. The solar diffusers will be used about every week, the lamps every day.
The OLI will also observe the moon monthly. Detector to detector normalization within a band is required to be
better than 0.5%; the diffuser observations will be key in maintaining this relative calibration.
Plane) Radiator ^
FPE (Focal Plane
Baseplate Struts to
ISE Assy (Instrument
Figure 1. Operational Land Imager
Table 1: OLI Spectral Bands
Electronics (ISEI— — —
, Subsystem Surwal
Figure 2. OLI Block Diagram
PRE-LAUNCH TESTING AND RESULTS
The principal spatial and geometric characterizations
(rsc, . the OLI instrument were performed in a thermal
vacuum chamber using the BATC horizontal
collimator assembly (HCA). The HCA includes
various targets at the focus of the collimator that are
***** used to test edge response, bright target recovery,
ghosting and line of sight. Edge response as opposed
modulation transfer function was used as the primary
hlo< measure of spatial response for the OLI. Figure 3
shows samples of the OLI edge response, where all requirements were met.
Figure 3. OLI edge response for the 30-meter band
Spectral and radiometric testing of the OLI was performed at BATC with the OLI in a thermal vacuum chamber
and with the spectral and radiometric sources outside. Testing included in-band relative spectral response,
linearity, stability, noise, and absolute calibration. Band average relative spectral responses are shown in Figure
4, and have been released to the web: http://ldcm.nasa.gov/spacecraft_instruments/oli_band_average.html . In
Figure 5 are shown the median Signal to Noise ratios of the OLI bands at typical radiance levels (L^p), i.e., about
a 10% reflectance at a 45° solar zenith angle.
The OLI for LDCM has been completed, delivered and integrated onto the LDCM spacecraft. It meets the vast
majority of its performance requirements with a few minor exceptions.
Vegetation - Bare desert — CA ^^Blue Green —Red — Nl R * — Pan ^—SWIRl ^—SWIR2 Cirrus
Figure 4. OLI band average relative spectral responses.
OU Sfgnal-fo- Noise Performance at (.typical
• OU SNR Requirement (median At Uypf ■ QU S*rR Performance (12-blt median At Lr^p]
Figure 5. OLI Signal to Noise Performance
 J.R. Irons and J.L. Dwyer, “An Overview of the Landsat Data Continuity Mission,” Proceedings of the SPIE, Vol. 7695, 12 May 2010.
 D. Reuter et al., “The Thermal Infrared Sensor on the Landsat Data Continuity Mission,” IGARSS 2011, p 754-757, Honolulu, HI.