VirtuScope: development of a high-fidelity virtual microscope simulation system for histology education

Abstract

Background

Microscope operation is a core skill in morphological laboratory education. However, traditional instructional approaches often face limitations in equipment accessibility, procedural guidance, and hands-on opportunities. With the advancement of virtual simulation technologies, new pathways have emerged for improving practical skill training. This study presents the development of VirtuScope, a high-fidelity virtual microscope simulation system, and explores its application value in histology education.

Methods

VirtuScope was developed as a standalone virtual simulation system for microscopes, featuring 1:1 3D structural reconstruction and high-fidelity simulation of physical interactions and optics, powered by advanced human-computer interaction and computer graphics. Key simulation features include focus adjustment, objective switching, and light source control. In the instructional design, VirtuScope was integrated into a blended teaching model combining video guidance, self-directed practice, and progressive transition to real microscope use. Student feedback and learning outcomes were evaluated using pre- and post-course questionnaires and knowledge tests.

Results

Students rated the system highly in terms of image clarity, interactivity, and instructional support. Most participants reported improved understanding of microscope structure and operation, and over 90% expressed willingness to use VirtuScope in future learning. Knowledge test scores showed significant post-course improvement (p < 0.001), and the overall recommendation rate reached 98.52%.

Conclusion

VirtuScope demonstrates strong adaptability and educational support capacity. Its visual, interactive, and repeatable features enhance learning efficiency and practical competence, offering a scalable complement to traditional microscopy training. Moreover, it provides a feasible solution for institutions with limited laboratory resources, extending access to high-quality microscopy education across diverse learning environments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12909-026-09416-z.

Introduction

Morphological laboratory courses are fundamental components of medical education, encompassing disciplines such as histology, embryology, anatomy, and pathology. These courses aim to cultivate students’ observational skills and practical competence by enabling them to identify the structural features of normal and diseased human tissues [1, 2]. As a central instrument in these courses, the optical microscope plays a critical role in the effectiveness of both teaching and learning [3].

Despite structured instruction on microscope usage at the beginning of the course, many students continue to face operational difficulties [4, 5]. To better understand these challenges, classroom observations and student surveys were conducted over several semesters. Eight common categories of operational issues were identified (Table 1), including improper handling, inadequate focusing, incorrect lens switching, misplacement of tissue sections, inappropriate oil immersion techniques, and insufficient post-use maintenance. Notably, some of these errors (e.g., incorrect interpupillary distance adjustment or failure to clean the oil immersion lens) persisted even in advanced courses, indicating limitations in current teaching approaches to reinforce long-term operational proficiency.

Table 1.

Common Microscope Operational Errors and Frequency Ratings Among Medical Students

No.	Category of Error	Description	Frequency
1	Improper carrying method	Holding the microscope by the stage instead of the arm or base	★★☆☆☆
2	Incorrect coarse/fine focus adjustment	Misuse of focusing knobs, leading to blurry or out-of-focus images	★★★★☆
3	Misoperation during objective lens switching	Failure to hear the “click” sound or to center the lens properly	★★★★☆
4	Slide misplacement or inadequate fixation	Misalignment of the slide on the stage; loose or improperly clamped specimen	★★★★☆
5	Incorrect use of oil immersion lens	Applying oil on non-oil objectives or failing to clean the oil after use	★★★☆☆
6	Inappropriate interpupillary distance or diopter adjustment	Misalignment of eyepieces or ignoring diopter calibration	★★★★☆
7	Mishandling or damaging cover slips and glass slides	Excessive pressure, broken or chipped slides	★★☆☆☆
8	Lack of post-use maintenance	Not lowering the stage, switching to low power, or covering the microscope after use	★★★★☆

This table summarizes the most commonly observed microscope operation issues among medical students during histology and pathology laboratory courses. Frequency ratings are based on observational data and student surveys conducted across multiple semesters. ★★ indicate that the problem is low-frequency (< 20%), ★★★ indicates medium-frequency (20–50%), and ★★★★ indicate high-frequency (> 50%)

In addition to individual skill gaps and limited time for instruction, hardware limitations, especially in resource-limited areas, also hinder effective microscopy-based instruction [6]. In response, we developed VirtuScope, a high-fidelity virtual microscope simulation system featuring 1:1 three-dimensional (3D) structural reconstruction and realistic simulation of physical interactions and optical behavior through advanced human–computer interaction and computer graphics. The system aims to replicate real-world microscope operation on digital platforms, enabling students to explore structural components, practice manipulation, and receive interactive feedback. By offering an accessible and repeatable learning environment, VirtuScope is expected to improve operational competence, enhance engagement, and alleviate disparities in resource distribution.

The integration of VirtuScope into morphological science curricula not only addresses the existing challenges in microscope training but also exemplifies the transformative potential of digital innovation in medical education. This project seeks to establish a reproducible and scalable instructional paradigm that bridges traditional laboratory training with immersive, technology-enhanced learning experiences.

Materials and methods

System architecture and 3D modeling

A high-fidelity virtual microscope simulation system (VirtuScope) was developed as a standalone desktop application. The 3D model of the microscope was constructed using Blender, based on the structural characteristics of a real optical microscope [7]. After completing geometric construction, the appearance of the instrument is simulated by means of basic material configuration, light simulation and UV mapping. The resulting model was further optimized for real-time rendering and interactive manipulation in an educational environment.

System implementation and interaction logic

The system was implemented using the OpenGL rendering engine in combination with the Dear ImGui interface library [8]. To ensure accurate and responsive user interaction, off-screen rendering techniques were employed to enable precise object selection and real-time feedback [9]. VirtuScope supports key microscope operations, including coarse and fine focus adjustment, objective lens switching, and illumination control, thereby replicating the standard workflow of optical microscopy.

Digital specimen processing and visualization

Digital specimens were derived from real histological images and stored in PNG format. Image processing and loading were performed using the OpenCV library. During runtime, the system dynamically calculates the current field of view based on user interactions and extracts the corresponding region from high-resolution images for rendering. In addition, the system adjusts image clarity in real time based on the focusing state, enabling realistic visualization of microscopic focusing details. At present, the system does not include a predefined case library, as it is primarily designed for histology education focusing on normal tissue structures. Future development will consider expanding the system to incorporate pathological cases.

User interface design and interaction workflow

The VirtuScope system incorporates a structured user interface designed to support core microscope operations within a 3D virtual environment. The interface integrates key functional modules, including specimen loading, objective lens switching, stage manipulation, and focus adjustment. Instructional components, such as embedded guidance prompts and video tutorials, are incorporated to facilitate self-directed learning. User interaction is implemented through mouse and keyboard inputs, enabling control of virtual microscope components. These include stage translation, nosepiece rotation, and illumination adjustment, corresponding to standard physical operations. The focusing mechanism is simulated through rotation of a virtual control knob, which dynamically modulates image sharpness to emulate depth-of-field variations in optical microscopy. To enhance procedural consistency, the system incorporates a predefined interaction workflow that guides users through sequential microscope operations. This workflow includes system feedback and instructional cues aligned with conventional laboratory protocols. The overall interface layout and interaction processes are illustrated in Figs. 3, 4 and 5.

Fig. 3.

User interface and instructional features of the VirtuScope system. A. Overview of the main interface. B-C. User interaction processes. D. Operational guidance panel. E-F. Embedded instructional videos supporting microscope training

Fig. 4.

Core interactive functions of VirtuScope. A. Stage movement: (a) to (b) represents vertical displacement. B. Specimen image transition from out of focus (a) to in focus (b). C. Objective switching demonstration: from 4× (a) to 10× (b). D. Effect of light intensity adjustment on image brightness: (a) to (b) shows transition from dark to bright

Fig. 5.

Logical workflow diagram of VirtuScope, illustrating user input and corresponding system responses within the simulation environment

Focus simulation based on optical defocus modeling

The focusing mechanism was simulated based on the circle of confusion principle combined with a Gaussian blur algorithm [10]. When the virtual specimen deviates from the focal plane, controlled blur is introduced to mimic optical defocus effects. A quantitative mapping was established between the rotation of the coarse and fine focus knobs and the resulting image sharpness. As users adjust the focus, the system dynamically modulates blur intensity, producing a continuous transition between focused and defocused states, thereby approximating real optical behavior. Gaussian blur was implemented by dynamically adjusting kernel parameters in response to focal displacement, enabling realistic simulation of out-of-focus imaging [11]. Further technical details on the circle of confusion model and optical parameter settings are provided in Supplementary Material 1, while the mathematical formulation of the Gaussian blur implementation is described in Supplementary Material 2.

Educational implementation and study design

This study was conducted within a histology laboratory course for first-year undergraduate medical students at Shantou University Medical College. VirtuScope was integrated into laboratory sessions as a supplementary training tool during the second semester of the 2024–2025 academic year. A total of 519 students participated in the study, including those enrolled in clinical medicine, stomatology, optometry, and psychiatry programs across both five-year and eight-year training tracks. A pre- and post-intervention questionnaire (see Supplementary Materials 3 and 4) design was employed to evaluate the effectiveness of the system.

Data collection and statistical analysis

The questionnaire employed a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). The internal consistency of the questionnaire was assessed using Cronbach’s alpha, yielding a value of 0.87, indicating good reliability. Differences in students’ responses before and after the intervention were analyzed using the Chi-square test, with statistical significance set at p < 0.05. All statistical analyses were performed using SPSS, while data visualization was conducted using GraphPad Prism.

Results

Development and structural modeling of the VirtuScope system

VirtuScope is a high-fidelity virtual microscope simulation system designed to realistically replicate the structural composition and operational processes of an optical microscope. The overall technical architecture of the system is illustrated in Fig. 1. It integrates several core technologies, including high-precision 3D modeling and real-time rendering, interactive simulation logic, vision-based image defocus simulation, and cross-platform compatibility. Together, these technologies enable an immersive and authentic virtual microscopy training environment tailored for medical laboratory education.

Fig. 1.

Technical workflow diagram of the VirtuScope system

For the 3D modeling component, the system utilized Blender software to reconstruct the microscope structure based on measurements and design features of actual teaching microscopes. The virtual microscope is logically divided into two major subsystems: mechanical modules and optical components. The mechanical modules include the arm, base, stage, focusing knobs, nosepiece, and tube; the optical components include the light source, condenser, objective lenses, and eyepiece. Each part was modeled to scale and positioned according to real-world reference data to ensure anatomical accuracy and structural integrity.

To support realistic operation, the system incorporated animation binding and motion logic to define five key interactive components: (1) stage (horizontal translation), (2) coarse and fine focusing knobs (rotation), (3) revolving nosepiece (rotation), (4) light source adjustment module (rotation), and (5) eyepiece module (drag-and-rotate interaction). These defined mechanisms laid the foundation for the interactive behavior of the virtual microscope.

After modeling the geometry, the team applied texture mapping and surface rendering using 2D materials created from high-resolution photographs of real microscopes. Through UV mapping and basic material shaders, the system achieved a photorealistic appearance. In addition, the illumination intensity of the light source was calibrated to match real-life optical parameters, enhancing the visual authenticity of the scene. The finalized 3D microscope model (Fig. 2) not only closely resembles real-world hardware in appearance but also supports dynamic interaction, forming the technical basis for system development and educational deployment. The user interface design and interaction workflow are further illustrated in Figs. 3, 4 and 5.

Fig. 2.

Visualization of virtual microscope modeling and rendering effects. A. 3D structural modeling of the virtual microscope. (a) right anterolateral view; (b) left anterolateral view; (c) detail of the coarse and fine focus knobs; (d) detail of the stage; (e) detail of the eyepiece; (f) detail of the objective lens. B. Rendered images of the virtual microscope. (a) oblique 45° view; (b) top view; (c) lateral view; (d) front view

Implementation of VirtuScope in histology laboratory teaching

During the second semester of the 2024–2025 academic year, we piloted the use of VirtuScope in the histology laboratory course at Shantou University Medical College. Histology was chosen as the application setting because it typically represents the first formal exposure for first-year medical students to optical microscopy. As mastering microscope operation is a foundational skill in medical morphology education, this course provided an ideal platform for evaluating the integration of a virtual simulation system into early-stage laboratory instruction. The pilot covered students from the five-year clinical medicine, stomatology, optometry, and psychiatry programs, spanning the full semester and involving over 400 participants.

To enhance instructional efficiency and learner engagement, we restructured the traditional teaching approach. Instead of lecturing on microscope structure and usage at the podium, instructors used VirtuScope’s 3D visualization module to demonstrate the main components and mechanical movements of a compound microscope. This enabled students to gain a spatial understanding of the instrument before hands-on interaction. Students then engaged in guided self-directed learning by manipulating the virtual microscope to practice key operational steps such as adjusting the light source, switching objectives, focusing, and moving the stage. To further support their learning, the VirtuScope system incorporated step-by-step instructional videos that followed standard microscope operation protocols. Students could use these as references during practice, promoting procedural fluency and independent learning.

Once students had become proficient with the virtual interface, they transitioned to operating real microscopes in the laboratory. This blended training model, combining virtual simulation with physical practice, allowed students to approach real-world equipment with greater confidence and technical readiness. In subsequent sessions, students who encountered difficulties or needed to revisit specific operations were encouraged to use VirtuScope for review, thus enabling a personalized, iterative learning cycle. The overall teaching application process is illustrated in Fig. 6, outlining a progressive instructional flow from virtual orientation to hands-on practice.

Fig. 6.

Implementation of VirtuScope in histology laboratory teaching, instructional workflow illustrating the progression from virtual training to hands-on microscope operation

Analysis of student feedback and learning outcomes

To evaluate the practical effectiveness of the VirtuScope system in histology laboratory teaching, two rounds of structured surveys were conducted before and after the course implementation. A total of 430 valid responses were collected in the pre-survey and 408 in the post-survey.

The pre-survey revealed that 80.93% of students had used a microscope prior to university, with 98.56% of those experiences occurring during high school biology classes. However, 99.30% reported having received no formal microscope training after entering university, and only 0.70% had limited exposure through research participation. Regarding their perceptions, students generally considered the principles and procedures of microscopy to be relatively complex; 92.79% believed that mastering microscope operation is essential, and 90.70% emphasized the importance of demonstrative instruction. These findings suggest a strong student preference for structured and visualized approaches to microscopy education.

Post-survey results indicated that 91.67% of students had never used a virtual microscope system before. Most found the interface intuitive and user-friendly (90.93%) and reported that the system’s core functions—such as zooming, rotating, and focusing—met their learning needs (88.97%), though some expressed a desire for expanded functionality. In terms of satisfaction (Table 2), the system was rated highly for image clarity, instructional guidance (both text and video), and effectiveness in supporting first-time users. Operational smoothness and sample loading speed were also rated positively, with average scores above 75 out of 100.

Table 2.

Summary of student satisfaction and suggested improvements for the VirtuScope system

No.	Evaluation Dimension	Satisfaction (%)	Suggested Improvements (%)
1	Interface intuitiveness and ease of use	90.93%	–
2	Smoothness of operational workflow	84.56%	54.41%: Optimization of loading speed
3	Image clarity	82.73%	61.27%: Enhancement of image quality
4	Completeness of functional operations	88.97%	45.10%: Expansion of specimen library
5	Teaching aids (text/video prompts)	83.52%	41.18%: Addition of instructional tools (e.g., annotation, measurement)
6	Willingness to recommend to others	98.52%	–

This table presents student feedback on VirtuScope regarding usability, workflow, image quality, functionality, instructional support, and overall recommendation. While overall satisfaction was high across all dimensions, students primarily suggested improvements in loading speed, image quality, specimen library diversity, and the addition of instructional tools such as annotation and measurement functions.

Student feedback further highlighted the perceived educational benefits of VirtuScope. As shown in Figs. 7A and 90.93% reported improved understanding of standard microscope procedures, 84.07% gained clearer knowledge of microscope components, 65.20% better understood the working principles, and 63.24% became more aware of common operational errors. Students expressed willingness to use VirtuScope in various learning contexts, including initial exposure to microscopy (89.46%), post-class review (40.69%), exam preparation (50.00%), pre-lab practice for senior-level courses (34.31%), and remote learning (33.58%) (Fig. 7B). Additionally, to assess knowledge acquisition, we administered the same 10-item true/false test on microscope principles and operations in both surveys. Post-course results showed a statistically significant improvement in scores (p < 0.001, difference = − 19.42, 95% CI [–20.26, − 18.59], n = 408), with no significant differences across gender, age, or major (Fig. 7C). Notably, 98.52% of students indicated that they would recommend VirtuScope to their peers (Table 2).

Fig. 7.

Student evaluation of VirtuScope’s educational effectiveness. A Student-reported benefits of VirtuScope in facilitating real microscope operation (horizontal bar chart). B Preferred scenarios for future use of VirtuScope in histology learning (donut chart). C Comparison of student microscopy knowledge scores before and after using VirtuScope, showing significant improvement (T-test analysis)

In summary, student feedback indicates that the VirtuScope system shows promising effectiveness in enhancing cognitive understanding, engagement, and self-directed learning in basic laboratory education. Its visual, interactive, and repeatable features provide a practical and complementary approach to traditional optical microscopy instruction.

Discussion

This study demonstrates the feasibility and educational value of the VirtuScope virtual microscope simulation system in histology laboratory teaching. Based on student feedback and practical observations, VirtuScope demonstrated strong potential to support novice learners in understanding microscope structures, mastering basic operational steps, and enhancing classroom engagement. By leveraging high-precision structural modeling and interactive simulation, the system offers a training environment that closely approximates real microscope use. Its dual emphasis on agency and procedural fidelity distinguishes it from conventional virtual laboratory systems, which are often limited to passive demonstrations.

Our findings should be interpreted in the context of existing developments in virtual microscopy. The use of virtual microscopy in medical education has gained increasing attention over the past decade. In China, several institutions have developed virtual laboratory platforms, primarily targeting biology and chemistry through large-scale procedural simulations [12–14]. While some of these platforms have begun to incorporate virtual microscopes, they often present static models focused solely on digital slide viewing, with limited support for interactive operations or mechanical manipulation [12, 13]. A recent implementation of an interactive virtual microscope system in oral histopathology demonstrated encouraging outcomes, yet al.so highlighted notable limitations in simulating core mechanical components and operational procedures, such as focusing or stage movement [14]. These limitations are consistent with our findings, where students particularly valued the interactive and procedural features of VirtuScope that are often absent in existing platforms.

Internationally, the transition toward virtual microscopy has accelerated, particularly during the COVID-19 pandemic when physical lab access was restricted [15, 16]. Platforms such as QuPath Edu and OpenMicroanatomy have enabled learners to engage with digital slides, perform diagnostic annotations, and participate in collaborative reviews [17–19]. Studies have shown that these tools can enhance student performance, engagement, and satisfaction [20–23]. However, the majority of existing systems remain limited to virtual slide navigation and lack structured training in the procedural mechanics of optical microscopes—such as adjusting coarse and fine focus, switching objectives, or modifying illumination settings [24–26]. This aligns with our results, which indicate that procedural interactivity plays a critical role in improving students’ understanding of microscope operation and engagement. Against this backdrop, VirtuScope fills an important pedagogical gap by integrating high-fidelity structural modeling with dynamic procedural interactivity. Unlike conventional systems that emphasize passive observation, VirtuScope enables students to engage directly with the microscope’s physical architecture and simulate real-time manipulation of its mechanical parts. This level of interactivity provides learners with a more immersive and authentic training experience, supporting the development of operational skills that are often underemphasized in existing digital platforms.

In this study, we redesigned the laboratory teaching process by using VirtuScope as a scaffold for introductory microscope instruction. Rather than relying on in-class verbal explanations by instructors, students were guided through 3D structural presentations, interactive manipulation exercises, and embedded instructional videos. This progressive exposure enabled students to gain early familiarity with core functions before transitioning to physical microscope use. The gradual shift from virtual to real-world practice supported effective knowledge transfer, lowered the entry barrier for hands-on operation, and allowed for self-paced, adaptive learning in later sessions. Student responses reflected strong approval of this blended approach, suggesting the feasibility of using simulation-based tools to enhance procedural skills training.

Beyond the local context of this study, VirtuScope also presents promising implications for regions with limited educational resources. In many under-resourced universities, rural schools, or vocational institutions, access to functional optical microscopes is constrained by funding, equipment shortages, and maintenance issues. As a lightweight and self-contained simulation platform, VirtuScope offers a low-barrier alternative for foundational training, even under “zero-equipment” conditions. This could broaden access to standardized laboratory education and potentially support early-stage science learning in secondary schools, bridging a longstanding equipment gap.

Nonetheless, this study has several limitations. First, the evaluation of the VirtuScope system relied primarily on student feedback and learning outcomes. Although these measures provide valuable insights into user experience and perceived educational benefits, they may be subject to response bias. Future studies could incorporate expert evaluation, such as faculty assessment of system usability, instructional alignment, and fidelity to real microscope operation, to provide a more comprehensive validation of the system. Some students reported moderate delays in sample loading and image rendering, particularly on computers with limited processing power. This issue stems primarily from the use of high-resolution digital specimens, which require significant resources for decoding and real-time rendering. In future iterations, we plan to optimize performance through image tiling and progressive loading strategies. Additionally, feedback highlighted limitations in sample library diversity and the absence of annotation and measurement tools. To address these concerns, we have already scanned and categorized multiple types of histological sections. Functional enhancements such as overlay markers and interactive measurement modules will also be introduced to improve usability and instructional alignment. With continued development, VirtuScope holds promise as a sustainable, adaptable platform for advancing microscope-based education across both traditional and remote learning environments.

Conclusion

This study demonstrated the feasibility and educational value of the VirtuScope virtual microscope simulation system in histology laboratory instruction. By leveraging high-precision 3D structural modeling and interactive logic simulation, VirtuScope created a training environment that closely mirrors real microscope operation. The system effectively supported students in understanding structural components, mastering procedural steps, and enhancing engagement in laboratory learning. Implementation results suggest that VirtuScope not only optimized instructional workflows but also offered a practical solution to common challenges in microscopy education, particularly in resource-limited settings.

Amid the broader trend of digital transformation in medical education, VirtuScope’s visual interactivity, modular scalability, and low deployment threshold present a promising direction for diversifying laboratory teaching modalities. Its adaptable architecture allows for potential implementation across under-resourced institutions, remote regions, and even secondary or vocational education settings. Future system iterations will focus on improving image loading efficiency, expanding specimen diversity, and enhancing instructional support tools. Through these ongoing developments, VirtuScope may help foster a more inclusive, sustainable, and widely accessible paradigm for microscope-based education.

Authors’ contributions

Yang Gao and Zhongjing Su conceived and supervised the study. Weixin Huang, Xiaoting Li, Xiaotong Cao, and Kaiqi Zhang performed the 3D structural modeling of the virtual microscope, developed the interactive simulation interface, and implemented the system functions. Yuwei Lin collected the data, including student recruitment, questionnaire administration, and preliminary analysis. Minwen Zhan and Jingyan Chen coordinated software installation across classroom computers and provided technical guidance during instructional sessions. Yang Gao and Weixin Huang designed the teaching application workflow and prepared the figures. Weixin Huang drafted the manuscript. Zhongjing Su and Yang Gao critically revised the manuscript. All authors reviewed and approved the final version.

Funding

This study was supported by the Guangdong Provincial Undergraduate Higher Education Teaching Reform Project (No. 673, 2023), the Guangdong Basic and Applied Basic Research Foundation (2025A1515011338), and the Guangdong Provincial Graduate Education Innovation Program (2025KCJS-043), as well as the Scientific Research Foundation for Talents of Shantou University (NTF22008) and the Teaching Quality Enhancement Project of Shantou University Medical College (2025-03).

Data availability

The VirtuScope software (Version 1.0) is publicly available in a GitHub repository at: https://github.com/weixinhum2023/VirtuScope.The datasets generated and analyzed during the current study are available from the corresponding author upon reasonable request.

Declarations

Ethics approval and consent to participate

This study was approved by the Ethics Committee of Shantou University Medical College (SUMC-2026-004). Written informed consent was obtained from all participants prior to their inclusion in the study. All procedures were conducted in accordance with relevant institutional guidelines and the ethical principles of the World Medical Association’s Declaration of Helsinki.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.