An apparatus for candling eggs includes a waterproof housing having a free end, a light source configured to emit visible light from the housing free end and illuminate an egg positioned adjacent to the housing free end, and a photodetector that generates an output signal corresponding to intensity of light from the light source leaving the egg. The photodetector is shielded from external light and from direct light from the light source. The light source and photodetector are disposed within the waterproof housing, and a replaceable bumper is removably secured to the housing free end. The bumper is configured to engage an egg in contacting relation therewith, and to shield the photodetector from external light and from direct light from the light source. A processor processes output signals from the photodetector to identify cyclical variations in light intensity and/or non-cyclical variations in light intensit本發明揭示一種用光檢查蛋之設備，其包含一具有一自由端之防水外殼、一經組態以自該外殼自由端發射可見光並照明一毗鄰該外殼自由端定位之蛋之光源，及一產生一對應於來自該光源之光離開該蛋之強度之輸出信號之光偵測器。該光偵測器經遮蔽以免受外部光及免受來自該光源之直射光之影響。該光源及光偵測器安置於該防水外殼內，且一可替換擋板可移除地固定至該外殼自由端。該擋板經組態以使一蛋與其嚙合成接觸關係，且遮蔽該光偵測器以免受外部光及免受來自該光源之直射光之影響。一處理器處理來自該光偵測器之輸出信號以識別光強度之週期變化及/或光強度之非週期變化。
