Modern stereoscopic 3DTV brings new QoE (quality of experience) to viewers, which not only enhances the 3D sensation due to the added binocular depth, but may also induce new problems such as visual discomfort. Subjective quality assessment is the conventional method to assess the QoE. However, the conventional perceived image quality concept is not enough to reveal the advantages and the drawbacks of stereoscopic images in 3DTV. Higher-level concepts such as visual experience were proposed to represent the overall visual QoE for stereoscopic images. In this paper, both the higher-level concept quality indicator, i.e. visual experience and the basic level concepts quality indicators including image quality, depth quantity, and visual comfort are defined. We aim to explore 3D QoE by constructing the visual experience as a weight sum of image quality, depth quantity and visual comfort. Two experiments in which depth quantity and image quality are varied respectively are designed to validate this model. In the first experiment, the stimuli consist of three natural scenes and for each scene, there are four levels of perceived depth variation in terms of depth of focus: 0, 0.1, 0.2 and 0.3 diopters. In the second experiment, five levels of JPEG 2000 compression ratio, 0, 50, 100, 175 and 250 are used to represent the image quality variation. Subjective quality assessments based on the SAMVIQ method are used in both experiments to evaluate the subject's opinion in basic level quality indicators as well as the higher-level indicator. Statistical analysis of result reveals how the perceived depth and image quality variation affect different perceptual scales as well as the relationship between different quality aspects.