Optical low pass filter

An optical low pass filter comprising:

• a plurality of optical elements bonded together and defining a bonded interface between each of the plurality of optical elements, the plurality of optical elements are quartz crystal plates;
• and
• at least one adhesion layer including an adhesive, the at least one adhesion layer having an average thickness of 5 to 15 μm and a difference between a thickest portion and a thinnest portion of the adhesion layer being 4 μm or less, wherein
• the plurality of optical elements being provided with an adhesion layer of the at least one adhesion layer at each bonded interface between the plurality of optical elements, and
• the low pass filter having a transmitted wave aberration of ±1.5λ or less (where λ represents an incident wavelength).