Most of the braille embossers incorporate a mode for the creation of braille embossed graphics (BEG). Some of them can produce dots in different elevations, but also various dot densities. Dot elevation and dot density constitute the main variables that dominate the identification and conceptualization by blind users of tactile elements, such as lines and areas, in BEG. Nevertheless, there are not enough published research data in this domain. We present the results of a study with 30 congenitally blind participants to examine their detection performance in tactile identification of context-free embossed lines and square areas in eight dot elevations H1 to H8 (from 0.03 to 0.47 mm) and two dot densities (10 and 20 dpi). The detection accuracy and response time of the matching task were examined for each type of test stimuli. The results of correct and misclassified stimuli are presented in confusion matrixes, along with the overall mean response time for each task. The participants classify with better accuracy the stimuli with the three lower dot elevations (between 0.03 mm and 0.15 mm) for both types of stimuli and in both dot densities. The minimum overall mean response time of the identification task was achieved for the larger dot height H8 in the case of raised-dot square areas of 10 dpi. The analysis of the results indicates that better classification accuracy is achieved with the combination of four dot heights H1, H2, H4, and H8. Blind users can distinguish textures produced by dots with very low heights in line with the recent literature suggestions. The current study constitutes a first step toward recommendations for the designers of BEG in applying textures with variable dot height and dot density for educational purposes or for producing tactile maps to benefit users who are blind.

大多数盲文浮雕都包含一种用于创建盲文浮雕图形（BEG）的模式。其中一些可以产生不同高度的点，但也可以产生不同的点密度。点高和点密度构成了主要变量，这些变量主导了BEG中盲人对触觉元素（如线条和区域）的识别和概念化。然而，在这个领域没有足够的公开研究数据。我们提出了一项研究结果，与30位先天失明的参与者一起，研究了他们在8个点高H1至H8（从0.03至0.47毫米）和两个点密度（10和10点高）的无上下文浮雕线和正方形区域的触觉识别中的检测性能。 20 dpi）。针对每种类型的测试刺激，检查匹配任务的检测准确性和响应时间。正确和错误分类的刺激的结果与每个任务的总体平均响应时间一起显示在混淆矩阵中。参与者可以对两种类型的刺激和两种点密度的三种较低的点高（在0.03 mm至0.15 mm之间）的刺激进行更好的分类。在10 dpi的凸起点正方形区域中，对于较大的点高度H8，可以实现识别任务的最小总体平均响应时间。结果分析表明，结合四个点高H1，H2，H4和H8，可以实现更好的分类精度。盲人可以根据最近的文献建议来区分高度非常低的点产生的纹理。