diff --git a/alembic/versions/a3f7c19b2d40_add_objective_lens_diameter_to_scope_infos.py b/alembic/versions/a3f7c19b2d40_add_objective_lens_diameter_to_scope_infos.py
new file mode 100644
index 0000000..e40f380
--- /dev/null
+++ b/alembic/versions/a3f7c19b2d40_add_objective_lens_diameter_to_scope_infos.py
@@ -0,0 +1,28 @@
+"""add_objective_lens_diameter_to_scope_infos
+
+Revision ID: a3f7c19b2d40
+Revises: 8012c00b0c04
+Create Date: 2026-08-04 00:00:00.000000
+"""
+
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision: str = "a3f7c19b2d40"
+down_revision: Union[str, None] = "8012c00b0c04"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "scope_infos",
+        sa.Column("objective_lens_diameter_mm", sa.Float(), nullable=True),
+    )
+
+
+def downgrade() -> None:
+    op.drop_column("scope_infos", "objective_lens_diameter_mm")