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Two-photon polymerization (TPP) has become one of the most popular techniques for stereolithography at very high resolutions. When printing relatively large structures at high resolutions, one of the main limiting factors is the printing time. The purpose of this paper is to present a new slicing algorithm to minimize printing times.

Typically, slicing algorithms used for TPP do not take into account the fact that TPP can print at a range of resolutions (i.e. with different heights and diameters) by varying parameters such as exposure time, laser power, photoresist properties and optical arrangements. This work presents multiresolution layered manufacturing (MLM), a novel slicing algorithm that processes 3D structures to separate parts manufacturable at low resolution from those that require a higher resolution.

MLM can significantly reduce the printing time of 3D structures at high resolutions. The maximum theoretical speed-up depends on the range of printing resolutions, but the effective speed-up also depends on the geometry of each 3D structure.

MLM opens the possibility to significantly decrease printing times, potentially opening the use of TPP to new applications in many disciplines such as microfluidics, metamaterial research or wettability.

There are many instances of previous research on printing at several resolutions. However, in most cases, the toolpaths have to be manually arranged. In some cases, previous research also automates the generation of toolpaths, but they are limited in various ways. MLM is the first algorithm to comprehensively solve this problem for a wide range of true 3D structures.

The purpose of this article is to introduce the themed section of History of Education Review on “The History of Knowledge and the History of Education”, comprising four empirical articles that together seek to bring the history of education into fuller dialogue with the approaches and methods of the nascent field of the history of knowledge.

This introductory article provides a broad overview of the history of knowledge for the benefit of historians of education, introduces the four themed section articles that follow, and draws out some of their overarching themes and concepts.

The history of knowledge concept of “arenas of knowledge” emerges as generative across the themed section. Authors also engage with problems of the legitimacy of knowledges, and with pedagogy as practice. In addition, focusing on colonial and postcolonial contexts raises reflexive questions about history of knowledge approaches that have so far largely been developed in European and North American scholarship.

The history of education has not previously been strongly represented among the fields that have gone into the formation of the history of knowledge as a synthetic, interdisciplinary approach to historical studies. Nor have historians of education much engaged with its distinguishing concepts and methodologies. The themed section also extends the history of knowledge itself through its strong focus on colonial and postcolonial histories.