diff --git a/src/stdatamodels/jwst/datamodels/schemas/miri_lrs_psf.schema.yaml b/src/stdatamodels/jwst/datamodels/schemas/miri_lrs_psf.schema.yaml
index 17eb85fd..d7785968 100644
--- a/src/stdatamodels/jwst/datamodels/schemas/miri_lrs_psf.schema.yaml
+++ b/src/stdatamodels/jwst/datamodels/schemas/miri_lrs_psf.schema.yaml
@@ -39,6 +39,6 @@ allOf:
       title: Wavelength image
       fits_hdu: WAVE
       default: 0
-      ndim: 2
+      ndim: 1
       datatype: float32