3 6 Ke·2026-02-10 03:56Group 1 - The evolution of small advertisements in public restrooms has transitioned from handwritten notes and stickers to laser-engraved ads, indicating a significant technological advancement [1][3][5] - The use of laser technology for engraving has become a new trend, with incidents reported where individuals were caught using laser tools to create these ads in public restrooms [6][8] - The laser machines used for these engravings are categorized into two types: laser marking, which alters the surface without removing material, and laser engraving, which removes material to create deeper impressions [9][11] Group 2 - The permanence of laser-engraved ads poses challenges for municipal departments and cleaning staff, as traditional methods of removal are ineffective, requiring more labor-intensive solutions [11][13] - The speed of engraving by offenders is significantly faster than the time required for removal, highlighting the efficiency of the technology in illicit activities [15] - The affordability and portability of laser engraving machines have drastically changed since 2010, making them accessible for misuse in public spaces [17][20] Group 3 - The decline in prices of laser technology has led to a proliferation of both legitimate and illegitimate uses, with the market for laser engraving equipment expected to reach approximately 100 billion yuan by 2024 [40] - The rise of consumer-grade laser machines has opened new markets, allowing hobbyists and entrepreneurs to engage with laser technology directly, leading to innovative applications [41][42] - Companies like x-Tool have successfully tapped into the consumer market, achieving significant sales and expanding their product offerings to include various functionalities beyond traditional engraving [44][60]