A light receiving apparatus comprises a holographic optical device having a plurality of holograms recorded in a light receiving surface thereof. The holographic optical device is configured to diffract light of a predetermined wavelength incident thereon from different directions onto a common focal area. The holographic optical device is shaped such that a first vector normal to the light receiving surface at a first location thereon is oriented along a first direction and such that a second vector normal to the light receiving surface at a second location thereon is oriented along a second direction, the second direction being different from the first direction.

 
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> Seismic-data acquisition methods and apparatus

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