If you can't find many articles on your topic, you may want to try a periodical index which focuses on a specific academic field. Academic libraries often subscribe to this kind of subject index . One subject index that is particularly useful for finding literary criticism is the Modern Language Association's MLA International Bibliography , which includes scholarly writings on literature, languages, linguistics, and folklore. Ask your librarian to help you find a library near you where you can use this index, or to suggest other indexes that may be useful to you.
Don Ihde called the hypothesis being 'hyped' and referred to clear evidence about the use of optical tools by, ., Albrecht Dürer and Leonardo da Vinci and others. As well the 1929 Encyclopædia Britannica  contains an extensive article on the camera obscura and cites Leon Battista Alberti as the first documented user of the device as early as 1437.  Ihde states abundant evidence for widespread use of various technical devices at least in the Renaissance and . in Early Netherlandish painting .  Jan van Eyck 's 1434 painting Arnolfini Portrait shows a convex mirror in the centre of the painting. Van Eyck also left his signature above this mirror,  showing the importance of the tool. The painting includes a crown glass window in the upper left side, a rather expensive luxury at the time. Van Eyck was rather fascinated by glass and its qualities, which was as well of high symbolic importance for his contemporaries.  Early optical instruments were comparatively expensive in the Medieval age and the Renaissance.