Is not what you see, it is how you react to the image.

The Rorschach Test, inkblot test or Psychodiagnostik designed by a Swiss psychologist named Hermann Rorschach [1885-1922] it is quite simple. There are 10 official inkblot cards.

The performer shows the cards one by one to the patient, asking what they originally saw and what made them think that while carefully watching every move the patient makes. The images themselves are only one component of the test, whose focus is the analysis of the perception of the images.
It can be described as projective-type of test. In psychology, a projective test is a personality test designed to let a person respond to ambiguous stimuli, presumably revealing hidden emotions and internal conflicts. This is different from an “objective test” in which responses are analyzed according to a universal standard (for example, a multiple choice exam). The responses to projective tests are content analyzed for meaning rather than being based on presuppositions about meaning, as is the case with objective tests.

The general theoretical position behind projective tests is that whenever a specific question is asked, the response will be consciously-formulated and socially determined. These responses do not reflect the respondent’s unconscious or implicit attitudes or motivations. The respondent’s deep-seated motivations may not be consciously recognized by the respondent or the respondent may not be able to verbally express them in the form demanded by the questioner. Advocates of projective tests stress that the ambiguity of the stimuli presented within the tests allow subjects to express thoughts that originate on a deeper level than tapped by explicit questions. Projective tests lost some of their popularity during the 1980s and 1990s in part because of the overall loss of popularity of the psychoanalytic method and theories. Despite this, they are still used quite frequently.