# Coastal Zone Imager
*sensor . products*

Coastal optical imager flown on HY-1D.

## Specifications
- **product status**: operational
- **deployment context**: orbital
- **manufacturer**: cast
- **sensor**: {"instrument_family":"passive-optical","measurement_principle":"passive","spec_disclosure":"undisclosed"}
- **entity type**: sensor
- **last verified date**: 2026-06-15
- **verified by**: community
- **claim status**: agency-sourced
- **provider**: cast
- **attributes**: {"kind":"sensor","product_status":"operational","deployment_context":"orbital","manufacturer":"cast","description":"Coastal optical imager flown on HY-1D.","sensor":"{\"instrument_family\":\"passive-optical\",\"measurement_principle\":\"passive\",\"spec_disclosure\":\"undisclosed\"}"}
- **relevance**: in-scope

## Editorial
The Coastal Zone Imager (CZI) is a spaceborne passive optical instrument designed for ocean-colour monitoring and coastal observation. It has flown on the HY-1 ocean-colour satellite series.[^wmo-oscar-czi]

Resolution and swath differ by satellite generation. On HY-1A and HY-1B, CZI operated at 250 m ground sampling distance with a 500 km swath.[^wmo-oscar-czi] On HY-1C and HY-1D the design was substantially upgraded: ground sampling distance was improved to 50 m,[^eoportal-hy1c1d] and swath was extended to approximately 950 km by mosaicking imagery from two cameras, each covering a 32-degree field of view with a 1-degree overlap.[^pmcncbi-czi-hy1c]

The spectral configuration supports ocean-colour retrieval, vegetation index mapping, and optical time-series change detection.[^wmo-oscar-czi] The focal-plane array type is not disclosed in publicly available documentation.

## Compositional position
- hy-1d (missions) --[mission_payloads]--> Coastal Zone Imager
- hy-1c (missions) --[mission_payloads]--> Coastal Zone Imager

## Sources
- [wmo-oscar-czi] | WMO OSCAR instrument record: CZI | https://space.oscar.wmo.int/instruments/view/czi | tier=community | accessed=2026-06-15
- [eoportal-hy1c1d] | HY-1C/1D mission overview, eoPortal | https://www.eoportal.org/satellite-missions/hy-1c-1d | tier=community | accessed=2026-06-15
- [eoportal-hy1a] | HY-1A mission overview, eoPortal | https://directory.eoportal.org/satellite-missions/hy-1a | tier=community | accessed=2026-06-15
- [pmcncbi-czi-hy1c] | Out-of-Band Response for CZI Onboard HY-1C, PMC/Remote Sensing | https://pmc.ncbi.nlm.nih.gov/articles/PMC6163480/ | tier=peer-reviewed | accessed=2026-06-15
- [wmo-oscar-hy1c] | WMO OSCAR satellite record: HY-1C | https://space.oscar.wmo.int/satellites/view/hy_1c | tier=community | accessed=2026-06-15

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Source: https://eo-atlas.org/products/sensor/czi
Maintainer: SpectraWorks B.V. (CC-BY 4.0)