PROBLEM TO BE SOLVED BY THE INVENTION The object of the present invention is to provide an observation optical system having a high resolution and a small size, an observation imaging device provided with the observation optical system, an observation imaging system, an imaging lens system, and an adjustment method of the observation optical system is there.An observation optical system according to the present invention includes an objective lens system G1 and an imaging lens system G2 in order from the observation object side, and includes an objective lens system G1 An observation optical system for forming an observation object image on the image plane IP of the image pickup element by the imaging lens system G 2 and satisfies predetermined conditions.BACKGROUND OF THE INVENTION【課題】本件発明の課題は、解像度が高く、小型の観察光学系、当該観察光学系を備えた観察撮像装置、観察撮像システム、結像レンズ系及び観察光学系の調整方法を提供することにある。【解決手段】上記課題を解決するため、本件発明に係る観察光学系は、観察被写体側から順に対物レンズ系G1と、結像レンズ系G2とで構成され、対物レンズ系G1によって結像された観察被写体像を結像レンズ系G2により撮像素子の像面IPに結像させるための観察光学系であって、所定の条件を満足させるものとする。【選択図】図1
